Go to Notes and Bibliography Style
Go to Author-Date Style
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Chicago-style source citations come in two varieties: (1) notes and bibliography and (2) author-date. If you already know which system to use, follow one of the links above to see sample citations for a variety of common sources. If you are unsure about which system to use, read on.
Notes and Bibliography or Author-Date?
The notes and bibliography system is preferred by many working in the humanities—including literature, history, and the arts. In this system, sources are cited in numbered footnotes or endnotes. Each note corresponds to a raised (superscript) number in the text. Sources are also usually listed in a separate bibliography. The notes and bibliography system can accommodate a wide variety of sources, including unusual ones that don’t fit neatly into the author-date system.
The author-date system is more common in the sciences and social sciences. In this system, sources are briefly cited in the text, usually in parentheses, by author’s last name and year of publication. Each in-text citation matches up with an entry in a reference list, where full bibliographic information is provided.
Aside from the use of numbered notes versus parenthetical references in the text, the two systems share a similar style. Follow the links at the top of this page to see examples of some of the more common source types cited in both systems.
Most authors choose the system used by others in their field or required by their publisher. Students who are unsure of which system to use will find more information here.
For a more comprehensive look at Chicago’s two systems of source citation and many more examples, see chapters 14 and 15 of The Chicago Manual of Style.
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.
Contributors: Jessica Clements, Elizabeth Angeli, Karen Schiller, S. C. Gooch, Laurie Pinkert, Allen Brizee, Ryan Murphy, Vanessa Iacocca, Ryan Schnurr
Last Edited: 2018-03-09 12:49:13
General Model for Citing Web Sources in Chicago Style
Titles for Websites, Blogs, and Social Media: 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. 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.
Footnote or Endnote (N):
1. Firstname Lastname, “Title of Web Page,” Publishing Organization or Name of Website in Roman, publication date and/or access date if available, URL.
Corresponding Bibliographical Entry (B):
Lastname, Firstname. “Title of Web Page.” Publishing Organization or Name of Website in Roman. Publication date and/or access date if available. URL.
Electronic Books and Books Consulted Online
Electronic books are cited exactly as their print counterparts with the addition of a media marker at the end of the citation: Kindle edition, PDF e-book, Microsoft Reader e-book, Palm e-book, CD-ROM, 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, Fourth ed. Indianapolis: Hackett, 2010. Kindle edition.
1. Donald Davidson, Essays on Actions and Events (Oxford: Clarendon, 2001), https://bibliotecamathom.files.wordpress.com/2012/10/essays-on-actions-and-events.pdf.
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 (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 (in a book), list the first author in the note followed by et al. For the corresponding bibliographic entry, list all authors (up to 10).
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.
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
7. Richard G. Heck, Jr., “About the Philosophical Gourmet Report” last modified August 5, 2016. http://rgheck.frege.org/philosophy/aboutpgr.php
Heck, Jr., Richard G. “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
8. “Illinois Governor Wants to 'Fumigate' State's Government,” CNN online, last modified January 30, 2009, http://edition.cnn.com/2009/POLITICS/01/30/illinois.governor.quinn/.
"Illinois Governor Wants to 'Fumigate' State's Government.” CNN online. Last modified January 30, 2009. http://edition.cnn.com/2009/POLITICS/01/30/illinois.governor.quinn/.
Web Page with Unknown Publication Date and Author
9. “Band,” Casa de Calexico, accessed October 27, 2017. http://www.casadecalexico.com/band.
“Band.” Casa de Calexico. Accessed October 27, 2017. http://www.casadecalexico.com/band.
Blog titles should be set in italics and blog entries should be set in quotation marks. Generally, blog entries and comments 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.
1. J. Robert Lennon, “How Do You Revise?,” Ward Six (blog), September 16, 2010 (8:39 a.m.), http://wardsix.blogspot.com/2010/09/how-do-you-revise.html.
2. Susan Woodring, September 17, 2010 (3:40 a.m.), comment on J. Robert Lennon, “How Do You Revise?,” Ward Six (blog), September 16, 2010 (8:39 a.m.), http://wardsix.blogspot.com/2010/09/how-do-you-revise.html.
Note: If the word “podcast” is included in the title of the podcast, there is no need to repeat it enclosed in commas after that title. “Podcast audio” is used below, then, as an example placeholder and would not necessarily be required for this specific example.
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, accessed October 31, 2017, https://www.thisamericanlife.org/radio-archives/episode/622/who-you-gonna-call.
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. accessed October 31, 2017. https://www.thisamericanlife.org/radio-archives/episode/622/who-you-gonna-call.
Blank Form for Online Multimedia
1. Firstname Lastname of Performer, Writer or Creator, Title of Text, indication of format/medium, running time, publication date, URL.
Lastname, Firstname of Performer, Writer or Creator. Title of Text. Indication of Medium, Running Time. Publication Date. URL.