how to document internet sources in a research paper

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Reference List: Electronic Sources

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Note:  This page reflects the latest version of the APA Publication Manual (i.e., APA 7), which released in October 2019. The equivalent resource for the older APA 6 style  can be found here .

Important Note: Some electronic citations necessitate the use of brackets. APA style dictates that brackets should directly surround their content without spaces (e.g., [bracketed content] should look like this). When possible, include the year, month, and date in references. If the month and date are not available, use the year of publication. Additionally, APA 7 th  edition no longer requires the use of “Retrieved from” before URLs or DOIs; special exceptions, however, are made for resources that are unarchived. Including the retrieval date for these sources indicates to readers that the version of the work they retrieve may be different than what was originally used. 

Please note: the following contains a list of the most commonly cited electronic sources. For a complete list of how to cite electronic sources, please refer to the 7 th edition of the APA Publication Manual.

Webpage or Piece of Online Content

If the page names an individual author, cite their name first:

Lastname, F. M. (Year, Month Date). Title of page . Site name. URL

Price, D. (2018, March 23). Laziness does not exist . Medium. https://humanparts.medium.com/laziness-does-not-exist-3af27e312d01

If the resource was written by a group or organization, use the name of the group/organization as the author. Additionally, if the author and site name are the same, omit the site name from the citation.

Group name. (Year, Month Date). Title of page . Site name. URL

American Society for the Prevention of Cruelty to Animals. (2019, November 21). Justice served: Case closed for over 40 dogfighting victims . https://www.aspca.org/news/justice-served-case-closed-over-40-dogfighting-victims

If the page's author is not listed, start with the title instead. Additionally, include a retrieval date when the page's content is likely to change over time (like, for instance, if you're citing a wiki that is publicly edited).

Title of page . (Year, Month Date). Site name. Retrieved Month Date, Year, from URL

Tuscan white bean pasta.  (2018, February 25). Budgetbytes. Retrieved March 18, 2020, from  https://www.budgetbytes.com/tuscan-white-bean-pasta/

If the date of publication is not listed, use the abbreviation (n.d.). 

Author or Group name. (n.d.).  Title of page . Site name (if applicable). URL

National Alliance on Mental Illness. (n.d.). Mental health conditions . https://www.nami.org/Learn-More/Mental-Health-Conditions

Wikipedia Article

APA 7 treats Wikipedia articles as special instances of entries in reference works. Thus, there are a few differences between reference entries for pages on Wikipedia and those for generic webpages.

Title of article. (Year, Month Date). In  Wikipedia.  URL of archived version of page

Quantum mechanics. (2019, November 19). In Wikipedia . https://en.wikipedia.org/w/index.php?title=Quantum_mechanics&oldid=948476810

Wikipedia articles often update frequently. For this reason, the date refers to the date that the cited version of the page was published. Note also that the manual recommends linking to the archived version of the page, rather than the current version of the page on the site, since the latter can change over time. Access the archived version by clicking "View History," then clicking the date/timestamp of the version you'd like to cite.

Online Scholarly Journal Article: Citing DOIs

Please note: Because online materials can potentially change URLs, APA recommends providing a Digital Object Identifier (DOI), when it is available, as opposed to the URL. DOIs are an attempt to provide stable, long-lasting links for online articles. They are unique to their documents and consist of a long alphanumeric code. Many—but not all—publishers will provide an article's DOI on the first page of the document.

Note also that some online bibliographies provide an article's DOI but may "hide" the code under a button which may read "Article" or may be an abbreviation of a vendor's name like "CrossRef" or "PubMed." This button will usually lead the user to the full article which will include the DOI. Find DOIs from print publications or ones that go to dead links with doi.org's "Resolve a DOI" function, available on the site's home page .

APA 7 also advises writers to include a DOI (if available), even when using the print source.

Article from an Online Periodical with DOI Assigned

Lastname, F. M., & Lastname, F. M. (Year). Title of article. Title of Periodical, Vol.( Issue), page numbers. DOI

Drollinger, T., Comer, L. B., & Warrington, P. T. (2006). Development and validation of the active empathetic listening scale. Psychology & Marketing, 23 (2), 161-180. https://doi.org/10.1002/mar.20105

Article from an Online Periodical with no DOI Assigned

If an online scholarly journal article has no DOI and is published on a website, include the URL. If an online scholarly article has no DOI and is published on a database, do not include a URL or any database information. The only exception is for databases that publish articles that are in limited circulation (like ERIC) or that are only available on that particular database (like UpToDate). Note that retrieval dates are required for unarchived sources that are likely, or intended, to change over time. 

Perreault, L. (2019). Obesity in adults: Role of physical activity and exercise. UpToDate . Retrieved January 12, 2020, from https://www.uptodate.com/contents/obesity-in-adults-role-of-physical-activity-and-exercise

APA 7 th edition does not provide guidance on how to cite abstracts. However, if you only use information from the abstract but the full text of the article is also available, we advise you to add "[Abstract]" after the article or source name. If the full text is not available, you may use an abstract that is available through an abstracts database as a secondary source.

Online News Article

Note:  The format for this type of source depends on whether your source comes from a site with an associated newspaper.

If the source  does  come from a site with an associated newspaper, leave the title of the article unformatted, but italicize the title of the newspaper.

Lastname, F. M. (Year, Month Date). Title of article. Title of Publication . URL

Richards, C. (2019, December 9). Best music of 2019: Lana Del Rey sings lullabies about the end of America. Washington Post . https://www.washingtonpost.com/entertainment/music/best-music-of-2019-lana-del-rey-sings-lullabies-about-the-end-of-america/2019/12/06/6e82c5ec-15d8-11ea-a659-7d69641c6ff7_story.html

On the other hand, if the source  doesn't  come from a site with an associated newspaper, italicize the title of the article, but leave the name of the site unformatted.

Lastname, F. M. (Year, Month Date). Title of article . Name of publishing website. URL

Jones, J. (2020, May 10). Why flats dominate Spain's housing market . BBC. https://www.bbc.com/worklife/article/20200506-why-do-flats-dominate-spains-housing-market

Electronic or Kindle Books

It is not necessary to note that you have used an eBook or audiobook when the content is the same as a physical book. However, you should distinguish between the eBook or audiobook and the print version if the content is different or abridged, or if you would like to cite the narrator of an audiobook.

Lastname, F. M. (Year).  Title of book . Publisher. URL

Lastname, F. M. (Year).  Title of book [eBook edition]. Publisher. URL

Lastname, F. M. (Year). Title of book (N. Narrator, Narr.) [Audiobook]. Publisher. URL (if applicable)

Dissertation/Thesis from a Database

Lastname, F. M. (Year). Title of dissertation or thesis (Publication No.) [Doctoral dissertation or master’s thesis, Name of Institution Awarding Degree]. Database Name.

Duis, J. M. (2008). Acid/base chemistry and related organic chemistry conceptions of undergraduate organic chemistry students  (Publication No. 3348786) [Doctoral dissertation, University of Northern Colorado]. ProQuest Dissertations and Theses Global.

Entry in an Online Dictionary, Thesaurus, or Encyclopedia with a Group Author

Note:  An online dictionary, thesaurus, or encyclopedia may be continuously updated and therefore not include a publication date (like in the example below). If that’s the case, use “n.d.” for the date and include the retrieval date in the citation.

Institution or organization name. (Year). Title of entry. In Title of reference work . URL

Merriam-Webster. (n.d.). Braggadocio. In Merriam-Webster.com dictionary . Retrieved January 13, 2020, from https://www.merriam-webster.com/dictionary/braggadocio

Entry in an Online Dictionary, Thesaurus, or Encyclopedia with an Individual Author

Lastname, F. M. (Year). Title of entry. In F. M. Lastname (Ed.), Title of reference work (edition). Publisher. URL or DOI

Martin, M. (2018). Animals. In L. A. Schintler & C. L. McNeely (Eds.), Encyclopedia of big data . SpringerLink. https://doi.org/10.1007/978-3-319-32001-4_7-1

Note: If the dictionary, thesaurus, or encyclopedia does not include an edition, simply skip that step.

Lastname, F. M. or Name of Group (Year). Title of dataset (Version No.) [Data set]. Publisher. DOI or URL

Grantmakers in the Arts. (2019). Arts funding trends, United States, 1994-present (ICPSR 37337) [Data set]. National Archive of Data on Arts & Culture. https://www.icpsr.umich.edu/icpsrweb/NADAC/studies/37337

Graphic Data (e.g. Interactive Maps, Infographics, and Other Graphic Representations of Data)

Give the name of the organization or individual followed by the date and the title. If there is no title, in brackets, you should provide a brief explanation of what type of data is there and in what form it appears. Include the URL and the retrieval date if there is no publication date.

HatchMed. (2017). 8 ways to improve patient satisfaction [Infographic]. HatchMed.com. https://www.hatchmed.com/blog/2017/1/30/8-ways-to-improve-patient-satisfaction

Google. (n.d.). [Google Map of Purdue University]. Retrieved January 12, 2020, from https://www.google.com/maps/@40.4237095,-86.9233886,17z

Qualitative Data and Online Interviews

If an interview is not retrievable in audio or print form, cite the interview only in the text (not in the reference list) and provide the month, day, and year in the text. If the interview transcript is published in an online periodical, like a magazine, cite the interview the same way you would cite the medium where it is published, as shown below:

Schulman, M. (2019, December 8). Peter Dinklage is still punk rock. The New Yorker. https://www.newyorker.com/culture/the-new-yorker-interview/peter-dinklage-is-still-punk-rock

If it is an audio file or transcript published in a database, credit the interviewee as the author and use the following model:

Paynter, W. (1970, September 17). Interview with Will Paynter [Interview]. Studs Terkel Radio Archive; The Chicago History Museum. https://studsterkel.wfmt.com/programs/interview-will-paynter

Online Lecture Notes and Presentation Slides

When citing online lecture notes, be sure to provide the file format in brackets after the lecture title (e.g. PowerPoint slides, Word document).

Lastname, F. M. (Year, Month Date). Title of presentation [Lecture notes, PowerPoint slides, etc]. Publisher. URL

Smith, C. (2017, October 13). AI and machine learning demystified [PowerPoint slides]. SlideShare. https://www.slideshare.net/carologic/ai-and-machine-learning-demystified-by-carol-smith-at-midwest-ux-2017

Computer Software/Downloaded Software

Do not cite standard office software (e.g. Word, Excel) or programming languages. Provide references only for specialized software.

Lastname, F. M. or Name of Group. (Year). Title of software (Version No.). Publisher. URL

Maplesoft. (2019). Maple companion (Version 2.1.0). Cybernet Systems Co. https://www.maplesoft.com/products/MapleCompanion/

E-mails are not included in the list of references, though you should parenthetically cite them in your main text:

(E. Robbins, personal communication, January 4, 2001).

Online Forum or Discussion Posting

Lastname, F. M. or Name of Group [username]. (Year, Month Date). Title of post [Online forum post]. Publisher. URL

Stine, R. L. [RL__Stine]. (2013, October 23). I’m R.L. Stine and it’s my job to terrify kids. Ask me anything! [Online forum post]. Reddit. https://www.reddit.com/r/IAmA/comments/1p32dl/

Lastname, F. M. or Name of Group [@username]. (Year, Month Date). Content of the post up to the first 20 words [Tweet]. Site Name. URL

Note : If the tweet includes images, videos, or links to other sources, indicate that information in brackets after the content description. Also attempt to replicate emojis if possible.

National Geographic [@NatGeo]. (2020, January 12). Scientists knew African grays are clever, but now they’ve been documented assisting other members of their species—even strangers [Tweet; thumbnail link to article]. Twitter. https://twitter.com/NatGeo/status/1216346352063537154

Twitter Profile

Lastname, F. M. or Name of Group [@username]. (n.d.). Tweets [Twitter profile]. Retrieved Month Date, Year, from URL

MLA Style [@mlastyle]. (n.d.). Tweets [Twitter profile]. Retrieved January 12, 2020, from https://twitter.com/mlastyle

Facebook Post

Lastname, F. M. or Name of Group. (Year, Month Date). Content of the post up to the first 20 words [Type of post]. Site Name. URL

Note: If the Facebook post includes images, videos, or links to other sources, indicate that information in brackets after the content description. Also attempt to replicate emojis if possible.

U.S. Department of the Interior. (2020, January 10). Like frosting on a cake, snow coats and clings to the hoodoos at Bryce Canyon National Park in Utah [Image attached] [Status update]. Facebook. https://www.facebook.com/USInterior/photos/a.155163054537384/2586475451406120/?type=3&theater

Facebook Page

Lastname, F. M. or Name of Group. (n.d.). Home [Facebook page]. Site name. Retrieved Month Date, Year, from URL

Little River Canyon National Preserve (n.d.). Home [Facebook page]. Facebook. Retrieved January 12, 2020 from https://www.facebook.com/lirinps/

Instagram Photo or Video

Lastname, F. M. or Name of Group [@username]. (Year, Month Date). Content of the post up to the first 20 words [Type of post]. Site Name. URL

BBC [@bbc]. (2020, January 12). Skywatchers have been treated to the first full moon of 2020-known as a “wolf moon”-at the same time as a [Photograph]. Instagram. https://www.instagram.com/p/B7OkWqbBwcf/

Blog Post  

Lastname, F. M. (Year, Month Date). Title of post. Publisher . URL

Axelrod, A. (2019, August 11). A century later: The Treaty of Versailles and its rejection of racial equality. Code Switch, NPR . https://www.npr.org/sections/codeswitch/2019/08/11/742293305/a-century-later-the-treaty-of-versailles-and-its-rejection-of-racial-equality

YouTube or other Streaming Video

Last Name, F. M. [Username]. (Year, Month Date). Title of video [Video]. Streaming Service. URL

Lushi, K. [Korab Lushi]. (2016, July 3). Albatross culture 1 [Video]. YouTube. https://www.youtube.com/watch?v=_AMrJRQDPjk&t=148s

Note : The person or group who uploaded the video is considered the author. If the author’s name is the same as the username, you can omit the [Username].

Author, A. A. (Year, Month Date). Title of talk [Video]. TED. URL

Al-Mutawa, N. (2010, July). Superheroes inspired by Islam [Video]. TED. https://www.ted.com/talks/naif_al_mutawa_superheroes_inspired_by_islam#t-4909

Or (if on YouTube)

Username. (Year, Month Date). Title of talk [Video]. YouTube. URL

Tedx Talks. (2011, Nov. 15). TEDxHampshireCollege - Jay Smooth - How I learned to stop worrying and love discussing race [Video]. YouTube.  https://www.youtube.com/watch?v=MbdxeFcQtaU

Podcast Episode

Host, A. A. (Host). (Year, Month Date). Title of episode (No. if provided) [Audio podcast episode]. In Name of podcast . Publisher. URL

Prime, K. (Host). (2019, March 29). For whom the cowbell tolls [Audio podcast episode]. In Radiolab . WNYC Studios. https://www.wnycstudios.org/story/whom-cowbell-tolls

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Citing internet sources, internet sources - general information, special demands of internet sources.

• Copying Text without Plagiarizing

How to Cite Internet Sources

Print sources posted online, online versions of print periodicals, databases (like lexis-nexis), online journals, organization websites, topic websites, private websites, online video (like youtube), forums, listservs, chats, & bulletin boards, email & instant messages, i nternet vs. print sources.

Some professors will discourage you from using sources you find or access over the Internet. Although such restrictions may be excessive, there are reasons to be wary. It’s much easier to publish information on the Internet than to publish a book or periodical in print. Since it’s easier, Web posters are not always as careful to make sure that the information is accurate. For one thing, print publishing is more expensive, so many print publishers are careful not to make mistakes or to cut corners, in case what they publish turns out to be unreliable—and therefore useless. The seeming anonymity of the Internet also encourages some people to write things quickly, without checking to be sure of their facts or their conclusions. Most of us have had the experience of sending by email something we wrote quickly—perhaps when rushed or angry. Often these are things we wouldn’t print, sign, and mail, because those extra steps give us time to consider our words more carefully, and also because we recognize a higher expectation that things in print should be trustworthy.

N o Author, No Authority

In the context of writing in college, material from much of the Internet is less reliable than print sources because it’s hard to tell who wrote or posted it. As discussed in the section  Why Cite? , the essence of academic scholarship is a conversation among authors. On many websites, it’s difficult to determine the author of the material. If the site creator’s name is listed, it’s still sometimes hard to tell whether the information has been reprinted from some other source. If you reach a website through a search engine, you may have to find the site’s homepage or search around in the “contact” information in order to identify the author or the organization that sponsors the site. Even if you find the author’s name, Internet sources make it harder to tell what status that person has in his or her field. Is the author an expert, a fan, or just a crackpot? After finding a website that seems useful and tracking down the author’s name, you may need additional research (perhaps using Google) to learn whether the author has any claim to credibility.

But of course, countless reliable sources can be accessed on the web, and even unreliable sources have some uses in research writing. (See  Scholarly vs. Popular Sources  for more about unreliable sources.) These days, many students and scholars use Web sources extensively in research and teaching. But they take extra care to assess and report the provenance of these sources.

Types of Websites

In this guide’s discussion of Internet sources, we draw distinctions between various kinds of websites: those sponsored by  organizations , those devoted to a  single topic , and  private websites  that are maintained by a single person—often a devoted fan of the topic under discussion. To some degree, these categories distinguish more and less reliable sources of information. But the distinctions are neither clear nor entirely stable. Some organizations, while established leaders in their fields, have very few resources available to maintain and update their websites. Some private individuals, although hosting websites as a hobby, are experts in their fields and consider accuracy on their sites to be the highest priority. It’s often useful to identify your source in the body of your paper (and not just in your citation or footnote); this identification is especially important when you use material from the Internet. If you give a sense of what kind of Web source you’re using, the reader will be better able to understand the context of your evidence.

Basics of Citing Websites

When listing Internet sources in your References or Works Cited, the most important thing to remember is that your goal is to make it easy for a reader to consult your sources. (This same goal is paramount when listing print sources.) For most sites, that means you should include the  full  URL for the page you cite in your paper (the web address that begins “http”). But websites change, and the address you used won’t always be active when your reader tries to view a source. For that reason, it’s important to include both the date you accessed the site and also a full account of the person, group, or organization that sponsors the site. Knowing more about the author helps readers to assess the source and also, sometimes, to find the source when the website has been moved or revised.

The general form of a citation from an Internet source is:

Author’s name. Title of Document. Title of Website. Sponsor of Website. Date of Document. Date of Access. URL.

As you will see in the discussion of specific categories, however, some of these items may be hard to determine.

Avoiding Plagiarism

The ease of using electronic sources of any kind can make it harder to keep track of where the source ends and your original contribution begins—and you must always keep that distinction clear. See  How to Copy and Paste but Not Plagiarize  for advice about how to use electronic sources wisely.

Respecting Privacy

Most of this guide focuses on helping you subordinate sources to your own ideas. In general, we highlight your need to respect authors’  intellectual  or  property  rights, explaining how to give people credit for their ideas while distinguishing your own original contributions. But the ease of using electronic sources also raises dangers about what might be called  privacy  rights, leading you to make public words that the original author intended only as private communication. When someone speaks in public, participates in an interview, or publishes a piece of writing, he or she implicitly agrees that other people may refer to this material in research. But some electronic sources blur the line between public and private communication. (Private communications also have a different force of authority than deliberately published material; see  Scholarly vs. Popular Sources  for more information.)

If in doubt about whether a given text should be considered public or private, we urge you to check with the original author before quoting it in your own work. Although the following categories overlap, they may help you decide when more care is warranted to avoid an invasion of privacy. (1) Web versions of sources that also appear in print are generally safe to quote, since most print publishers take care to secure rights before publication. (2) Publicly accessible websites are generally safe to quote. You may occasionally find a website reposting information that’s clearly from category 3, in which case you may wish to contact the original author before using the material. But if you can access the information through regular surfing, without passwords, it’s probably safe to use. (3) Communications sent via email or accessed by membership in a specific group are generally considered private, and you should exercise care in quoting from them in your papers.

Even in this last category, there’s not a hard and fast rule you can follow. If your university sends an announcement to all students via email, you may reasonably consider this public information. If your best friend reveals something damaging or embarrassing in an email sent only to you, it’s clearly private. But what if a professor writes to you about something related to the course? Or if you receive a message that’s sent only to the members of a small club? What about the discussion forums that many courses set up for students to exchange ideas about the readings? These cases are all ambiguous. Unless there’s been an explicit agreement that the material is public, we encourage you to check before using such messages in your work.

Copying Text Without Plagiarizing

One convenience of using electronic sources is the ability—once you’ve selected the passages you wish to quote—to copy and paste quotations instead of having the retype them into your paper. Even before you begin drafting a paper, copying and pasting sections from your sources seems an easy way to take notes, so that you can look the material over later without surfing back to the website. This very convenience, however, also leads writers into danger. In the midst of researching and taking notes, it’s just too easy to paste quotations into your file with the intention to go back later and note down the source. When you return to your draft, it can be hard to distinguish your own writing from the passages you’ve copied.

As discussed in  Understanding and Avoiding Plagiarism , the worst consequence of failing to acknowledge sources is to yourself: if you paste in someone’s words as your own, you will miss the opportunity to add your commentary, and therefore miss an opportunity to grow as a thinker and writer. Most of this guide focuses on such intellectual reasons for working properly with sources, rather than emphasizing the penalties of plagiarism. But because the copy and paste technique is so common, it’s especially important to warn you about its potential for abuse. Every year students come before the Yale Executive Committee having committed plagiarism through pasting material from the Internet into their papers and then forgetting to go back and identify the sources. Even when the oversight seems unintentional, these students are guilty of plagiarism, and must face penalties.

But you can avoid this danger with one very simple precaution:

Every time you highlight material from a website to use in your paper, save the material to a new file. Copy the URL (the full web address that begins with “http”) at the top of the new file, and give the file a name that briefly identifies the website.

Taking this extra step will allow you to review your sources when you’ve made more progress with your paper. So if you were thinking of using a piece of this web page in your paper, you’d copy the relevant portion into a Word file, add the URL, and perhaps call the file “Writing at Yale Copy/Paste Advice.” You’ll still be able to avoid retyping by copying and pasting from the new file you’ve made. But you will have created a record of your excerpts to help you distinguish your sources from your own work. For your own convenience, you may also want to add other citation information below the URL—such as author and date of access—before moving on to examine the next website. See  Special Demands of Internet Sources  for more information about how to cite websites. See also  Scholarly vs. Popular Sources  for advice about how to use Internet sources effectively.

Note: Even when you properly identify Internet sources, the very pasting that feels like a time-saver can lead you to use block quotations that are longer and less precise than necessary. Many writers, especially beginning academic writers, are better served by retyping quotations, because this extra step leads them to edit quotations and to paraphrase. You could still cut and paste to help you keep track of interesting passages before deciding which ones to quote in your paper (remembering, as suggested above, to create a new file for each website you work with).

MLA: Aristotle.  Nicomachean Ethics . 350 B.C.E. Trans. W. C. Ross.  The Internet Classics Archives . Ed. Daniel C. Stevenson. 1994. Web. 20 May 2015. [author.] [ title .] [original publication date.] [ website name .] [website author.] [update date.] [medium.] [date of access.]

APA: Aristotle. (1994).  Nicomachean ethics . (W. C. Ross, Trans.). In D. C. Stevenson (Ed.),  The internet classics archives . (Original work published 350 B.C.E.). Retrieved from  http://classics.mit.edu/Aristotle/nicomachaen(link is external) [author, by last name.] [(posting date).] [ title. ] [website author, (“Ed.”),] [ website name .] [(original publication date).] [ Retrieved   from  URL]

Note: in APA style, no access date is necessary for information that will not be changed or updated, like an electronic book or a journal or newspaper article.

Also note: when a DOI (Digital Object Identifier) is available, list the DOI instead of the URL. (A DOI is a unique alphanumeric string assigned by a registration agency to identify content and provide a persistent link to its location on the Internet.)

Chicago: 16. Aristotle,  Nicomachean Ethics . [fn. #.] [author last name,  shortened t itle .] [Shortened Chicago reference; see  More Notes on Chicago Style  for more information.]

Note: In the Bibliography, Chicago style does not generally include date of access.

Also note: You may notice that listing Internet sources often takes more time and care than listing print sources. Since the authorship and location of Web sources are harder to establish, readers need even more information in order to assess sources and to retrieve them for further study. See  Special Demands of Internet Sources  for more information.

MLA: Scott, Janny, and David Leonhardt. “Shadowy Lines That Still Divide.”  New York  Times  15 May 2005. Web. 20 May 2015. [author.] [“article title.”] [ periodical title ] [publication date.] [medium.] [date of access.]

APA: Scott, J., & Leonhardt, D. (2005, May 15). Shadowy lines that still divide.  New York Times.  Retrieved from  http://www.nytimes.com/2005/05/15/national/class/OVERVIEW-FINAL.html?pagewanted=all&_r=0(link is external) [author.] [(publication date).] [article title.] [ periodical title. ] [ Retrieved from  URL]

Note: in APA style, no date of access is necessary for information that will not be changed or updated, like an electronic book or a journal or newspaper article.

Chicago: 17. Scott and Leonhardt, “Shadowy Lines.” [fn. #.] [author last name, “shortened title.”] [Shortened Chicago reference; see  More Notes on Chicago Style  for more information.]

If a print journal, magazine, or newspaper maintains a version of its publication URL online, articles that you cite are listed in your Works Cited or list of References by the name of the article’s author. In MLA style, the name is followed by the title of the article—in APA, the publication date comes after the author. (If no author is identified, list by the article’s title. In that case, be sure to give at least a few key words from the title in the body of your paper, so that readers know how to find the source in your bibliography.) Next list the title of the journal, magazine, or newspaper. Give the publication date of the article next for MLA, followed by the date that you accessed the site. For APA , give the full URL—the Web address that begins with “http.” When a DOI (Digital Object Identifier) is available, list the DOI instead of the URL. (A DOI is a unique alphanumeric string assigned by a registration agency to identify content and provide a persistent link to its location on the Internet.)

Note: If you use a database service (such as Lexis-Nexis) to access electronic sources, you must credit the database. See  Databases (like Lexis-Nexis)  for more information.

Also note: Although online versions of print sources are often more reliable than online journals or private websites, their reliability is no greater than that of their print versions. See  Scholarly vs. Popular Sources  for more information.

MLA: Wallis, Claudia, et al. “The New Science of Happiness.”  Time  17 Jan. 2005: A1-A55.  Academic Search Premier . Web. 20 May 2015. [author, by last name.] [“article title.”] [ periodical title ] [publication date]: full page numbers for article.] [ database name .] [medium.] [date of access.]

APA: Wallis, C., Coady, E., Cray, D., Park, A., & Ressner, J. (2005, January 17). The new science of happiness.  Time , A1-A55. Retrieved from Academic Search Premier [author(s), by last name, initial).] [(publication date).] [article title.] [ periodical title ,] [full page numbers for article.] [ Retrieved   from  database name or URL]

Chicago: 18. Wallis et al., “The New Science.” [fn. #.] [author last name, “shortened title.”] [Shortened Chicago reference; see  More Notes on Chicago Style  for more information.]

Also note: In the Bibliography, Chicago style adds the URL (the Web address that begins with “http”), and does not name the database service directly if that name is part of the Web address. For Chicago, as for APA„ when a DOI (Digital Object Identifier) is available, list the DOI instead of the URL. (A DOI is a unique alphanumeric string assigned by a registration agency to identify content and provide a persistent link to its location on the Internet.)

Several companies maintain databases that make it easier to find articles on the topic you’re researching. Using these databases is especially helpful for connecting you to scholarly sources, which have been vetted by experts in their field before publication. The Yale library system subscribes to many such databases, allowing you to access them for free. See  Scholarly vs. Popular Sources  for more information about using scholarly sources. If you use a service like this—such as Lexis-Nexis—to find an article that you then cite in your paper, you must include the database name in your Works Cited or list of References. (The principle is that you want your reader to know how to retrieve your source for further research.)

Note: You may notice that listing Internet sources often takes more time and care than listing print sources. Since the authorship and location of Web sources are harder to establish, readers need even more information in order to assess sources and to retrieve them for further study. See  Special Demands of Internet Sources  for more information.

Also note: Although online versions of print sources are often more reliable than  Online Journals  or  Private Websites , their reliability is no greater than that of their print versions. See  Scholarly vs. Popular Sources  for more information.

Hitchens, Christopher. “Unfairenheit 9/11.”  Slate  21 June 2004. Web. 20 May 2015. < http://www.slate.com/articles/news_and_politics/fighting_words/2004/06/unfairenheit_911.single>.(link is external)>. [author, by last name.] [“article title.”] [ online journal title ] [posting date.] [medium.] [date of access.] [.]

Note: MLA style does not require the use of URLs in citations of internet sources. However, some instructors may prefer that you use URLs. In this case, MLA suggests that the URL appear in angle brackets after the date of access.

APA: Hitchens, C. (2004, June 21). Unfairenheit 9/11.  Slate . Retrieved from  http://www.slate.com/articles/news_and_politics/fighting_words/2004/06/unfairenheit_911.single(link is external) [author.] [(posting date).] [article title.] [ online journal title. ] [ Retrieved from  URL]

Chicago: 19. Hitchens, “Unfairenheit 9/11.” [fn. #.] [author last name, “shortened title.”] [Shortened Chicago reference; see  More Notes on Chicago Style  for more information.]

An online journal is a website that publishes new material on a regular schedule (often weekly or monthly), with a journal title or other masthead, but that does not release a print publication. An online journal is not the same as the online version of a periodical that also publishes in print. (See  Online Versions of Print Periodicals .) The distinction matters, because online journals—while often more reliable than  private websites —are often considered less reliable than print sources or Internet versions of print sources. See  Scholarly vs. Popular Sources  for more information.

When including an article from an online journal in your Works Cited or list of References, list it by the name of the article’s author. This information is followed in MLA style by the article’s title, by the publication date in APA style. (If no author is identified, list by the article’s title.) Next list the online journal’s name. Give the publication date of the article (for MLA), followed by the date that you accessed the site. Finally, give the full URL—the Web address that begins with “http.” When a DOI (Digital Object Identifier) is available, list the DOI instead of the URL. (A DOI is a unique alphanumeric string assigned by a registration agency to identify content and provide a persistent link to its location on the Internet.)

MLA: Fangmann, Alexander. “Illinois Supreme Court Strikes Down Pension Cuts.” 11 May 2015.  World Socialist Web Site . Web. 20 May 2015. < https://www.wsws.org/en/articles/2015/05/11/illi-m11(link is external) >. [author, by last name.] [“section or page title.”] [posting date.] [ organization name. ] [date of access.] [.]

APA: Fangmann, A. (2015, May 11). Illinois Supreme Court strikes down pension cuts. Retrieved 20 May 2015, from the World Socialist Web Site: https://www.wsws.org/en/articles/2015/05/11/illi-m11(link is external) [author, by last name, initial.] [(posting date).] [page title.] [ Retrieved  date of access,] [ from  organization name:] [URL]

Chicago: 20. Fangmann, A. “Illinois Supreme Court.” [fn. #.] [author last name, “shortened title.”] [Shortened Chicago reference; see  More Notes on Chicago Style  for more information.]

Many organizations maintain websites hosting information about the organization or about the field that they work in. Some examples include commercial companies, universities, non-profit organizations, political groups, and government agencies. The reliability of these websites varies widely, as these organizations often use their websites to promote specific causes and may therefore emphasize only the facts and ideas that support their goals. See  Scholarly vs. Popular Sources  for more information.

But sometimes these organizations have the most comprehensive coverage of topics that pertain to them. For certain topics, it’s also useful to examine what the interested parties say, even if you must remember to balance it with research into other points of view. If you are conscientious about identifying who sponsors the site, your reader will be better prepared to examine the material you present. Websites hosted by university departments and programs would generally be considered reliable sources, especially in their areas of scholarly expertise. (More caution is warranted when the site discusses politics or issues of university governance. Be careful, too, to distinguish sites created by individual faculty members from those sponsored by the larger institution.)

Whenever possible, you should identify the author of the material you use from a website. Some pages you access will have separate titles or sub-titles, which can be used like the titles of an  article in a journal . This title is followed by the name of the main website, if there is one, and the name of the sponsoring organization. After this comes the full URL for the material you’re using.The final item is the date that you accessed the site.

Note: It’s sometimes hard to find the author of material on an organization website. In that case, list by the title of the site—if there is one—or by the name of the organization. If you can’t find any of this information, even after searching through the site’s links, you may be using a  private website  or  topic website , and should review the information for those sources.

MLA: “The Horcrux of Love.”  Mugglenet.com: The #1 Harry Potter Site . 3 Jan. 2013. Web. 20 May 2015. < http://www.mugglenet.com/2013/01/the-horcrux-of-love(link is external) >. [“section or page title.”] [ website name .] [posting date.] [medium.] [date of access.] [.]

APA: The horcrux of love. (2013, Jan. 3).  Mugglenet.com: The #1 Harry Potter site . Retrieved 20 May 2015, from  http://www.mugglenet.com/2013/01/the-horcrux-of-love(link is external) [section or page title.] [(posting date).] [ website name .] [ Retrieved  date of access,] [ from  URL]

Chicago: 21. “The Horcrux of Love.” [fn. #.] [“shortened title.”] [Shortened Chicago reference; see  More Notes on Chicago Style  for more information.]

Websites that are  print sources posted online ,  online versions of print periodicals ,  online journals , or  organization websites  are discussed separately. By “topic websites,” we mean sites that are dedicated to a single issue, such as the life of a famous person, the main ideas of a social movement, or the details of a popular television show. This category is a little hard to define. Unlike online journals or other periodicals, topic websites are not usually revised on a regular schedule, although material may be added from time to time. And unlike organization websites, topic websites do not usually promote the products or mission of a particular institution—which means they also don’t have the organization’s reputation to back up their authority. Finally, topic websites may also overlap with private websites, which often focus on a single issue that their author is passionate about.

Still, the category is worth knowing about, because a lot of background information on general topics like “Medieval Literature” or “Film Noir” is found on websites that don’t easily fit any of the other categories. You’ll want to double-check material you find on Topic Websites, and you may need to treat them as  popular sources  rather than  scholarly sources . If you take these precautions, topic websites are sometimes useful for giving a broad overview or putting you on the track of more authoritative sources. (See  Special Demands of Internet Sources  for more information.)

When these websites appear to be wholly or primarily the work of one author, list by the author’s name, followed by the title of the article or specific page you’re using (if there is one), the website title (often the name of the topic), the date of posting (if known), the date you accessed it, and the full URL—the Web address that begins with “http.”

If the site you’re using is sponsored by an organization of some kind (like a company, a university department, or a political group), it may qualify as an  organization website , and you should review the information for those sources.

MLA: Mohanraj, Mary Anne. “The Early Years: 1971-1985.”  Mary Anne Mohanraj . 20 May 2015. Web. < http://www.mamohanraj.com/BioPhotos/bio1.html> . [author.] [“section or page title.”] [ website name. ] [date of access] [medium.] [.]

APA: Mohanraj, M. A. The early years: 1971-1985.  Mary Anne Mohanraj . Retrieved May 20, 2015, from  http://www.mamohanraj.com/BioPhotos/bio1.html [author.] [section or page title.] [ website name .] [ Retrieved  date of access,] [ from  URL]

Chicago: 22. Mohanraj, “The Early Years.” [fn. #.] [author last name, “shortened title.”] [Shortened Chicago reference; see  More Notes on Chicago Style  for more information.]

Private websites come in many forms. Some dabble in multiple topics, about which the site’s author may not even profess any special expertise. Some announce themselves as fan sites, indicating that the author has an intense interest but no special background or credentials. Still others are quite professional in presentation, with authors who profess or demonstrate vast experience.

Just a few years ago, unreliable websites were often riddled with typographical errors or burdened with amateurish design and graphics. But it’s increasingly easy to host websites that look polished and professional, which can make it hard to judge whether the site’s sponsors take seriously the responsibility to check and update their information. For the purpose of academic research, most private websites should be considered popular sources, which can be useful as sources of opinion but should generally not be relied on for authoritative information. (See  Popular vs. Scholarly Sources  for more information.)

It’s often useful to identify your source in the body of your paper (and not just in your citation or footnote); this identification is especially important when you use private websites. If you give a sense of what kind of web source you’re using, the reader will be better able to understand the context of your evidence. Private websites also raise issues of privacy, as some sites that require password access may not invite republication of their material in scholarly research. See  Special Demands of Internet Sources  for more information.

When using material from a private website, list by the author (if known), then by the title of the article or specific Webpage you’re using (if known), and the date of posting (if listed). Follow this by the title of the website, if applicable. If the site is part of an identifiable online group (like “Facebook” or “tumblr”), include that title next. Next, list the date that you accessed the site and the full URL—the Web address that begins with “http.”

Some of these details may be hard to identify. In the example above, for instance, it was not possible to determine when the specific section of the website was last updated. Only the date of access is given.

MLA: Martin, George R. R. “A Few More Last Words.”  Not a Blog .  8 May 2010. Livejournal. Web. 20 May 2015. < http://grrm.livejournal.com/152340> . [author, by last name.] [“title of entry.”] [ title of weblog .] [posting date.] [site sponsor or publisher.] [medium.] [date of access.] [.]

APA: Martin, G. R. R. (2010, May 8). A few more last words [Weblog post]. Retrieved May 20, 2015, from Livejournal:  http://grrm.livejournal.com/152340 [author, by last name, initial.] [(posting date).] [title of entry [format description].] [Weblog post.] [ Retrieved  date of access,] [ from  site sponsor or publisher:] [URL]

Chicago: 23. Martin, “Last Words.” [fn. #.] [author last name, “shortened title.”] [Shortened Chicago reference; see  More Notes on Chicago Style  for more information.]

Blogs—an abbreviation of “weblogs”—are websites or areas of websites devoted to dated reflections by the site’s author. Many blogs are hosted on or presented as private websites where the author claims little special expertise or no professional affiliation relevant to the blog’s topic. In these cases, see the discussion of  Private Websites , and use the same care when evaluating the material you access.

But blogs are increasingly included as a feature of  organization websites  (Amazon.com, for instance, now invites authors to post blogs on their work) or as elements of  online versions of print periodicals  (the  New York Times  website hosts several blogs by reporters and editors). When using a blog that’s identified with a larger journal or organization, follow the advice listed for those general sources.

Even when hosted by a recognized organization, most blogs should probably be treated as popular rather than scholarly sources. See  Scholarly vs. Popular Sources  for more information.

The example above also lists “Livejournal” as the site’s sponsor. This information might be considered analogous to the organization that sponsors an  organization website . But in some cases, it may not be necessary to give the site sponsor. Livejournal, for instance, does not supervise posters’ comments very closely. A sponsor like “Facebook” has more rules and some restrictions to access, but is still doesn’t stand behind the material as much as an  online journal  would. When deciding whether to include the site sponsor, use your judgment: if the blog pursues a theme in common with the sponsor, list the sponsor.

Note: It’s often useful to identify your source in the body of your paper (and not just in your citation or footnote); this identification is especially important when you use blogs. If you give a sense of what kind of web source you’re using, the reader will be better able to understand the context of your evidence. See  Special Demands of Internet Sources  for more information.

The formats below cover the most common ways to cite video clips that were published online (on sites like YouTube and Vimeo). Video that was first published elsewhere but accessed online (on sites like Netflix and Hulu) is cited differently. See the notes that follow for more information.

MLA: TED. “Philip Zimbardo: The Psychology of Evil.” Online video clip.  YouTube . YouTube, 23 Sept. 2008. Web. 8 Aug 2015. < https://www.youtube.com/watch?v=OsFEV35tWsg>  [author’s name or screen name.] [“title of video.”] [media type.] [ name of website .] [site sponsor or publisher,] [posting date.] [medium.] [date of access.] [.]

APA: TED. (2008, Sept. 23).  Philip Zimbardo: The psychology of evil [Video file]. Retrieved Aug. 8, 2015, from  https://www.youtube.com/watch?v=OsFEV35tWsg [author’s name or screen name.] [(posting date).] [ title of entry [format description].] [ Retrieved  date of access,] [ from  URL]

Note: If you know both the author’s name and his or her screen name (and they are different from one another), APA style cites the author’s name first (last name, first initial) followed by the screen name in square brackets (e.g. Booker, J [jbook].).

Chicago: 24. TED, “Philip Zimbardo.” [fn. #.] [author name or screen name, “shortened title.”] [Shortened Chicago reference; see  More Notes on Chicago Style  for more information.]

Like other film and video formats, conventions for citing online video are less fixed than those for print or other kinds of online sources. The citation for a video clip that was first published online typically attributes the clip to the individual who posted it on the Internet. Video that was first published elsewhere before being posted online, is usually attributed to the individuals most responsible for making it—the director or performers. See the citation formats for Film & Video and Television, Radio Program, or Music Video for more information.   Depending on who seems most responsible for the existence of the video you’re citing, you may choose to attribute an online video to its creators rather than the individual who posted it. For example, a film that is released online or an ongoing web series, may be more accurately attributed to the director or actors than the person who uploaded it to the Internet. For citation formats that attribute video to the actors or director, see Film & Video and Television, Radio Program, or Music Video .  

MLA: Levy, Michael. “Re: your canon?” Science Fiction Research Association, 19 Apr. 2006. Web. 26 June 2006. < sfra-l@wiz.cath.vt.edu (link sends e-mail) >. [author, by last name.] [“title or subject line.”] [discussion group,] [posting date.] [medium.] [date of access.] [.]

APA: Levy, M. (2006, April 19). Re: your canon? [Electronic mailing list message]. Retrieved June 26, 2006 from  sfra-l@wiz.cath.vt.edu (link sends e-mail) . [author, by last name, initial.] [(posting date).] [title or subject line [format description].] [ Retrieved  date of access  from  address.]

Chicago: 24. Levy, “Re: your canon?” [fn. #.] [author last name, ”title or subject heading.”] [Shortened Chicago reference; see  More Notes on Chicago Style  for more information.]

There are many electronic forums that allow users with a specific interest or affiliation to discuss topics with each other. Some of these are restricted to members of a group, or of a specific course. (Many Yale courses, for instance, provide forum discussions through the Classesv2 server.) Other such discussions are open to any interested party. Although discussions limited to professionals in a field may be more authoritative, in general you should probably treat material from these forums as popular rather than scholarly sources. See  Scholarly vs. Popular Sources  for more information.

Note: Many such forums expect communications to be private. Be sure to check the group’s policies on reproduction of such material. Even if an FAQ or moderator seems to make reproduction permissible, a decent respect for privacy suggests that you secure the poster’s permission before making the material public.

If you use material from an electronic forum, list by author’s name. Follow that with the most specific identifying information you can give about the particular post. Depending on the type of discussion, there may be subject headings or specific message numbers on a given post. You may or may not be able to tell the posting date.

In MLA style, include the name of the sponsoring forum. Since most of these discussions do not supervise postings, do not put the sponsor name in italics. Follow this with the date you accessed the material. Even when membership is restricted to a particular organization, most listervs should probably be treated as popular rather than scholarly sources. See  Scholarly vs. Popular Sources  for more information.

The last item in your listing—the electronic address—brings up one point on which MLA and APA styles differ starkly: in APA, if the posting cannot be retrieved, you cite it in your paper as a personal communication and do not include it in your list of References. Even in MLA style, it’s better to cite the message in the form that’s most easily accessible to your reader: many listservs archive their messages on the web, for instance, even though the original postings are delivered by email. Try to include the archive address.

Also note: As discussed in  Signaling Sources , it’s often useful to identify your source in the body of your paper (and not just in your citation or footnote); this identification is especially important when you use listservs. If you give a sense of what kind of Websource you’re using, the reader will be better able to understand the context of your evidence. See  Special Demands of Internet Sources  for more information.

MLA: Donahue, Tiane. “Re: Your WPA Question.” Message to the author. 14 Dec. 2004. Email. [author, by last name.] [“title or subject line.”] [message recipient.] [message date.] [medium.]

APA: Do not include in list of References. Cite in your paper as a personal communication.

Chicago: 25. Tiane Donahue, “Re: Your WPA Question,” email message to author, December 14, 2000. [fn. #.] [author full name, “subject heading,”] [type of message,] [date of message.]

Note: Chicago style footnotes give full information for private messages, but does not list them in the Bibliography.

It’s probably obvious that the authority of material that comes in private communications varies greatly with the status of the source. What someone writes to you by email may be useful as a source of opinion, but can seldom be relied on as definitive information, unless you’re in correspondence with a recognized expert. And even in these cases, the informality of email makes most authors much less careful about checking facts and conclusions, rendering the information less authoritative. Most email messages should probably be treated as popular rather than scholarly sources. See  Scholarly vs. Popular Sources  for more information.

Note: Most people consider email to be private. Even if the message is sent to more than one recipient, a decent respect for privacy suggests that you secure the sender’s permission before making the material public. If you received the message as a forward, the obligation to seek permission is even more urgent, as the original author likely has no reason to expect you to use the message in your own work. See  Special Demands of Internet Sources  for more information.

If you do use material from an email, the format for listing in MLA style is fairly simple, as in the example above: Author, Subject, “Email to the author,” and Date.

In APA style, you do not include in your list of References any source that can’t be retrieved by your reader. If you use email in your paper, cite it as a personal communication in your text, and do not list it at the end. For Chicago style, private messages are given full citation in a footnote, but not included in the Bibliography.

Note: As discussed in the section on  Signaling Sources , it’s often useful to identify your source in the body of your paper (and not just in your citation or footnote); this identification is especially important when you use private messages. If you give a sense of what kind of source you’re using, the reader will be better able to understand the context of your evidence. See  Special Demands of Internet Sources  for more information.

MLA: “King Arthur.”  Wikipedia, The Free Encyclopedia . Wikimedia Foundation, Inc., 18 May 2015. Web. 20 May 2015. < http://en.wikipedia.org/wiki/King_Arthur(link is external) >. [“page title.”] [ website name. ] [site sponsor or publisher,] [date of last revision.] [medium.] [date of access.] [.]

APA: King Arthur. (n.d.). In  Wikipedia . Retrieved July 26, 2006, from: http://en.wikipedia.org/wiki/King_Arthur(link is external) [page title.] [(“n.d.”).] [ In  website name.] [ Retrieved  date, from: URL]

Chicago: 26. “King Arthur.” [fn. #.] [“title.”] [Shortened Chicago reference; see  More Notes on Chicago Style  for more information.]

To list material from Wikipedia, you should review the advice for  organization websites . But Wikipedia merits additional attention because of its recent growth and popularity. Some professors will warn you not to use Wikipedia because they believe its information is unreliable. As a community project with no central review committee, Wikipedia certainly contains its share of incorrect information and uninformed opinion. And since it presents itself as an encyclopedia, Wikipedia can sometimes seem more trustworthy than the average website, even to writers who would be duly careful about  private websites  or  topic websites . In this sense, it should be treated as a popular rather than scholarly source. See  Popular vs. Scholarly Sources  for more information.

But the main problem with using Wikipedia as an important source in your research is not that it gets things wrong. Some of its contributors are leaders in their fields, and, besides, some print sources contain errors. The problem, instead, is that Wikipedia strives for a lower level of expertise than professors expect from Yale students. As an encyclopedia, Wikipedia is written for a common readership. But students in Yale courses are already consulting primary materials and learning from experts in the discipline. In this context, to rely on Wikipedia—even when the material is accurate—is to position your work as inexpert and immature.

If you use Wikipedia for general background, check several other sources before using the material in your essays. Some of the facts you find may be attributable to common knowledge (see  Common Knowledge  for more discussion). You may also be able to track opinions or deeper ideas back to their original sources. In many cases, your course readings will contain similar ideas in better, more quotable language. Many student writers are tempted to use Wikipedia for definitions of terms (the same way a beginning writer might quote a dictionary). But in most cases, a definition drawn or paraphrased from the primary course readings—or from other scholarly sources—will be more effective. See  Why Cite?  for more discussion of definitions and keyterms.

Of course, if you do use language or information from Wikipedia, you must cite it—to do otherwise constitutes plagiarism. The advice here is not to hide what Wikipedia contributes to your ideas, but rather to move beyond Wikipedia and write from a more knowledgeable, expert stance.

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A publication of the harvard college writing program.

Harvard Guide to Using Sources 

• The Honor Code
• Citing Sources

Citations provide information to help your audience locate the sources you consulted when writing a paper or preparing a presentation. Some of your instructors will specify which citation format you should use; others will tell you to choose your own citation format as long as you use it consistently. The most common citation formats are MLA (Modern Language Association) style, which is primarily used for papers in the humanities; APA (American Psychological Association) style, which is primarily used for papers in the social sciences; and Chicago style (The Chicago Manual of Style), which is used for both humanities and social science papers.

Some of your courses at Harvard will require you to use other citation formats. Some science courses may require you to use the citation style of the American Medical Association (AMA). AMA style is considered a standard citation format for academic writing in the sciences and is used in many textbooks and medical journals. The AMA Manual of Style is available online . The American Chemical Society publishes its own style guide , which you may be asked to use in chemistry courses. The Harvard Department of Economics provides students with a departmental style guide, which you can find  here . If you are not sure which format to use for a specific course, consult your instructor.

Both APA and MLA styles require you to credit your sources in two ways. First, you must include a parenthetical citation in the text of your paper that indicates the source of a particular quotation, paraphrased statement or idea, or fact; second, you must include a list of references at the end of your paper that enables readers to locate the sources you have used. You can read more about MLA style here and APA style here .

Chicago style also requires you to credit your sources both in the text and at the end of your paper. Chicago offers guidance on two types of in-text citations–notes or parenthetical citations. You can read more about Chicago style here .

If you have questions about which citation style to use, you should always check with your instructor.

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• Research Process
• Find Background Info
• Find Sources through the Library
• Evaluate Your Info
• Cite Your Sources
• Evaluate, Write & Cite

• is the right thing to do  to give credit to those who had the idea
• shows that you have read and understand  what experts have had to say about your topic
• helps people find the sources  that you used in case they want to read more about the topic
• provides   evidence  for your arguments
• is professional and  standard practice   for students and scholars

What is a Citation?

A citation identifies for the reader the original source for an idea, information, or image that is referred to in a work.

• In the body of a paper, the  in-text citation  acknowledges the source of information used.
• At the end of a paper, the citations are compiled on a  References  or  Works Cited  list. A basic citation includes the author, title, and publication information of the source. 

From:  Lemieux  Library,  University  of Seattle 

Why Should You Cite?

Quoting Are you quoting two or more consecutive words from a source? Then the original source should be cited and the words or phrase placed in quotes. 

Paraphrasing If an idea or information comes from another source,  even if you put it in your own words , you still need to credit the source.  General vs. Unfamiliar Knowledge You do not need to cite material which is accepted common knowledge. If in doubt whether your information is common knowledge or not, cite it. Formats We usually think of books and articles. However, if you use material from web sites, films, music, graphs, tables, etc. you'll also need to cite these as well.

Plagiarism is presenting the words or ideas of someone else as your own without proper acknowledgment of the source. When you work on a research paper and use supporting material from works by others, it's okay to quote people and use their ideas, but you do need to correctly credit them. Even when you summarize or paraphrase information found in books, articles, or Web pages, you must acknowledge the original author.

Citation Style Help

Helpful links:

• MLA ,  Works Cited : A Quick Guide (a template of core elements)
• CSE  (Council of Science Editors)

For additional writing resources specific to styles listed here visit the  Purdue OWL Writing Lab

Citation and Bibliography Resources

• How to Write an Annotated Bibliography
• << Previous: Evaluate Your Info
• Next: Evaluate, Write & Cite >>

Creative Commons Attribution 3.0 License except where otherwise noted.

Land Acknowledgement

The land on which we gather is the unceded territory of the Awaswas-speaking Uypi Tribe. The Amah Mutsun Tribal Band, comprised of the descendants of indigenous people taken to missions Santa Cruz and San Juan Bautista during Spanish colonization of the Central Coast, is today working hard to restore traditional stewardship practices on these lands and heal from historical trauma.

The land acknowledgement used at UC Santa Cruz was developed in partnership with the Amah Mutsun Tribal Band Chairman and the Amah Mutsun Relearning Program at the UCSC Arboretum .