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Web Sources

Summary:

This section contains information on The Chicago Manual of Style method of document formatting and citation. These resources follow the seventeenth edition of The Chicago Manual of Style, which was issued in 2017.

General Model for Citing Web Sources in Chicago Style

Titles for Web Sources:

The title of a website that is analogous to a traditionally printed work but does not have (and never had) a printed counterpart can be treated like titles of other websites. For example, Wikipedia can be treated as a website, rather than as a conventional encyclopedia. This is a departure from previous editions of CMOS.

Titles of websites should follow headline-style capitalization and are usually set in roman without quotation marks. Sections of a website, such as a specific header, an individual page, a single blog entry, etc. should be written in roman with quotation marks. There are, however, some exceptions: titles of blogs are set in italics and titles of books, journals, television shows, movies, and other types of works should be treated the same whether cited as a print version or an online version. For example, when citing the website of the television news station CNN, the title maintains italics. Furthermore, in cases such as this, when a website does not have a distinctive title, it can be cited based on the entity responsible for the website, for instance, CNN online. If in doubt regarding whether to use roman or italics, roman is the safer choice.

Authors for Web Sources:

The author of web content is often not immediately clear. If a name is given, use the name as you would in any other source. If the content is published under a screen name, internet handle, or pseudonym, and the author’s real name is not available, use this in place of the author’s name. When a web page's author cannot be determined, simply list the title first. Note, however, that entries for sources without authors come before entries for sources with authors in the bibliography.

Dates for Web Sources:

If the source you are citing has a clear publication date, use that as the source’s date, following standard guidelines. Otherwise, look for a revision date; many websites will make note of when they were last modified, edited, or revised. If you are using a date of revision rather than a date of publication, make that clear: “Last modified May 17, 2019”. You may use both at your discretion, in which case you should distinguish between the two: “Published April 26, 2019; last modified May 17, 2019”. If no date at all is available, use the date at which you accessed the source to get the data: “Accessed August 7, 2019”. If the site is modified again so that the data you retrieved originally is altered or removed, you should add a note to that effect in either the text or the citation, specifying “as of [date]” if possible.

Web Source Examples in Chicago Style

Footnote or Endnote (N):

1. Firstname Lastname, “Title of Web Page,” Name of Website, Publishing Organization, publication or revision date if available, access date if no other date is available, URL.

Corresponding Bibliographical Entry (B):

Lastname, Firstname. “Title of Web Page.” Name of Website. Publishing organization, publication or revision date if available. Access date if no other date is available. URL .

Electronic Books and Books Consulted Online

Electronic books (e-books) are cited exactly as their print counterparts with the addition of a media marker at the end of the citation: Kindle, PDF, EPUB, etc. Books consulted online are also cited exactly as their print counterparts with the addition of a DOI (or URL) at the end of the citation. See also Books.

Note: Stable page numbers are not always available in electronic formats; therefore, you may include the number of chapter, section, or other easily recognizable locator instead.

Weston, Anthony. A Rulebook for Arguments, 4th ed. Indianapolis: Hackett, 2010. Kindle.

N:

1. Donald Davidson, Essays on Actions and Events (Oxford: Clarendon, 2001), https://bibliotecamathom.files.wordpress.com/2012/10/essays-on-actions-and-events.pdf.

B:

Davidson, Donald, Essays on Actions and Events. Oxford: Clarendon, 2001. https://bibliotecamathom.files.wordpress.com/2012/10/essays-on-actions-and-events.pdf.

Online Periodicals (Journal, Magazine, and Newspaper Articles)

Online periodicals are cited exactly as their print counterparts with the addition of a DOI or URL at the end of the citation. See also Periodicals. Also keep in mind that while access dates are not required for formally published electronic sources (e.g., journal articles), they can be useful for informally published electronic sources or may be required for by some disciplines for all informally and formally published electronic sources. Access dates should be located immediately prior to the DOI or URL.

For four or more authors, list the first author in the note followed by et al. For the corresponding bibliographic entry, list all authors (up to 10).

N:

1. Kirsi Peltonen et al. “Parental Violence and Adolescent Mental Health,” European Child & Adolescent Psychiatry 19, no. 11 (2010): 813-822, doi: 10.1007/s00787-010-0130-8.

B:

Peltonen, Kirsi, Noora Ellonen, Helmer B. Larsen, and Karin Helweg-Larsen. “Parental Violence and Adolescent Mental Health.” European Child & Adolescent Psychiatry 19, no. 11 (2010): 813-822. doi: 10.1007/s00787-010-0130-8.

Web Page with Known Author and Date

N:

7. Richard Kimberly Heck, “About the Philosophical Gourmet Report,” last modified August 5, 2016, http://rgheck.frege.org/philosophy/aboutpgr.php.

B:

Heck, Richard Kimberly. “About the Philosophical Gourmet Report.” Last modified August 5, 2016. http://rgheck.frege.org/philosophy/aboutpgr.php.

Web Page with Known Date but without Known Author

N:

8. “Illinois Governor Wants to 'Fumigate' State's Government,” CNN online, January 30, 2009, http://edition.cnn.com/2009/POLITICS/01/30/illinois.governor.quinn/.

B:

"Illinois Governor Wants to 'Fumigate' State's Government.” CNN online. January 30, 2009. http://edition.cnn.com/2009/POLITICS/01/30/illinois.governor.quinn/.

Web Page with Unknown Publication Date and Author

N:

9. “Band,” Casa de Calexico, accessed October 27, 2017, http://www.casadecalexico.com/band.

B:

“Band.” Casa de Calexico. Accessed October 27, 2017. http://www.casadecalexico.com/band.

Blog

Blog titles should be set in italics and blog entries should be set in quotation marks. Generally, blog entries are cited only as notes. If you frequently cite a blog, however, then you may choose to include it in your bibliography. Note: if the word “blog” is included in the title of the blog, there is no need to repeat it in parentheses after that title.

N:

1. J. Robert Lennon, “How Do You Revise?,” Ward Six (blog), September 16, 2010, http://wardsix.blogspot.com/2010/09/how-do-you-revise.html.

Social Media

Posts on social media will often be cited only as notes, though if you intend to discuss the content in depth, you should also put a citation in the bibliography. Since it is easy – and common – for social media posts to vanish with little notice, it is advisable to take a screenshot or similar record of anything you intend to cite, so that future edits or deletions will not undermine your work. Please note that all of this applies only to public content on social media. Private content, such as a direct message or a post in a restricted-membership group should be cited as a personal communication.

Social media posts do not typically have titles, so if a title is not provided, simply use the text of the post, retaining all original capitalization, spelling, etc., set in roman with quotation marks. Do not include more than 160 characters in this section of the citation; if the post is longer than that, cut it off (with an ellipsis) at a sensible point before the 160-character mark is reached. Citation of a social media post should fit the following format:

N:

1. Firstname Lastname (Screen name), “Post text”, social media service, indication of format/medium, publication date, time stamp, URL

B:

Lastname, Firstname (Screen name). “Post text”. Social media service, indication of format/medium, publication date, time stamp. URL.

Ideally, a post should be cited by the author’s legal name and screen name / internet handle, but if there is no screen name available (e.g. on a Facebook post) or no legal name available (e.g. on a Twitter post), use whichever you do have. Also note that you needn’t include the format/medium if the post is only text, and you should only include the time stamp if it is relevant to your point or necessary to distinguish between multiple citations on the same day. Also, if you have quoted the full post in your main text, you can leave that out of your note citation.

N:

2. Bill Nye (@BillNye), “While I’m not much for skipping school, I sure am in favor of calling attention to the seriousness of climate change. Our students can see the problem…,” Twitter, March 14, 2019, https://twitter.com/BillNye/status/1106242216123486209.

B:

Nye, Bill (@BillNye). “While I’m not much for skipping school, I sure am in favor of calling attention to the seriousness of climate change. Our students can see the problem….” Twitter, March 14, 2019. https://twitter.com/BillNye/status/1106242216123486209.

Forums and Mailing Lists

Citations for internet forums or mailing lists are very similar to social media citations, with a few differences. Rather than the text of the post, use the thread title or subject heading as your citation title; also, the name of the list or forum should be added in addition to the host site or service.

N:

3. u/labtec901, “Accepted Undergrad Questions Megathread,” r/Purdue, Reddit, January 14, 2019, https://www.reddit.com/r/Purdue/comments/ag3841/accepted_undergrad_questions_megathread/.

B:

u/labtec901. “Accepted Undergrad Questions Megathread.” r/Purdue, Reddit, January 14, 2019. https://www.reddit.com/r/Purdue/comments/ag3841/accepted_undergrad_questions_megathread/.

Comments

At times, it may be necessary to cite a comment someone has made on a blog entry, online article, social media post, etc. Generally, the comment will only be cited as a note, not in the bibliography, unless there is some significant reason you feel it should be considered a source on its own, separate from the work to which it was responding. Citation of a comment need only contain the name of the commenter (and/or screen name, as above), the date the comment was made (time stamp optional), and a reference back to the work to which it is responding.

N:

2. Susan Woodring, September 17, 2010 (3:40 a.m.), comment on Lennon, “How Do You Revise?.”

B:

Woodring, Susan. September 17, 2010 (3:40 a.m.). Comment on Lennon, “How Do You Revise?.”

Online Multimedia

Online multimedia should be cited using the general format below. Note that whether the title of the work should be set in italics or in roman with quotation marks will vary from one medium to another, as noted near the beginning of this page. For additional guidelines on the citation of videos, songs, and multimedia in general, see Audiovisual Recordings and Other Multimedia.

N:

1. Firstname Lastname of Creator, Title of Work, additional contributors, publishing organization, publication date, indication of format/medium, running time, URL.

B:

Lastname, Firstname of Creator. Title of Work. Additional contributors. Publishing organization. Publication date. Indication of format/medium, running time. URL.

Podcast

When citing a podcast, set the podcast title in italics, and the episode title (and number, if it is included in the title of the episode) in roman with quotation marks. The date of publication should be included after the episode title rather than before the medium, as shown below.

Note: Inclusion of the word “podcast” follows the same guidelines as inclusion of the word “blog” above. “Podcast, MP3 audio” is used below, then, as an example placeholder and would not necessarily be required for this specific example.

N:

1. Sean Cole and Ira Glass, “622: Who You Gonna Call?,” August 4, 2017, in This American Life, produced by WBEZ, podcast, MP3 audio, 1:00:27, https://www.thisamericanlife.org/radio-archives/episode/622/who-you-gonna-call.

B:

Cole, Sean and Ira Glass. “622: Who You Gonna Call?.” Produced by WBEZ. This American Life. August 4, 2017. Podcast, MP3 audio, 1:00:27. https://www.thisamericanlife.org/radio-archives/episode/622/who-you-gonna-call.

Online Video

If you are citing a video from an online service, such as YouTube, you can follow the general multimedia guidelines, but you must include the URL. The medium for any sort of streaming video where the file type is not necessarily clear or relevant can be cited simply as “video”.

N:

1. Alejandra Ortega, “Grammar: Active and Passive Voice,” Purdue OWL, February 1, 2019, video, 4:22, http://youtu.be/GEP-8lFTKKg.

B:

Ortega, Alejandra. “Grammar: Active and Passive Voice.” Purdue OWL. February 1, 2019. Video, 4:22. http://youtu.be/GEP-8lFTKKg.