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.
Please also note that these examples refer to Web pages retrieved from the free Internet. They do not refer to e-books, nor do they refer to articles from databases or online encyclopedias accessible through the library. For examples of citing these types of materials, click on the books, articles, and/or encyclopedias links to the left.
Section 14.245 of the Manual presents the elements of a webpage citation (which are in a slightly different order than a citation for a book or article):
- Webpage title (or a description of the page if there is no title)
- Webpage author (if any)
- The owner or sponsor of the site
- Publication, revision, or last updated date if any; if no date of this nature is available, include an access date
- Webpage address. Unlike in other citation styles, you do include a period at the end of a webpage address when citing webpages in the Chicago style.
Web Page, Author:
Kathie Nunley, "The Caffeine Craze of Youth," Layered Curriculum, accessed July 28, 2008. http://help4teachers.com/caffeine.htm.
Web Page, Group Author:
United Nations Platform for Action Committee, “Globalization and Clothes,” Women and the Economy, last modified March 2011,
Web Page, No Author:
"Leave no Veteran Behind: A Special Court Tries to Keep Troubled Veterans out of Prison,” The Economist, June 2, 2011,
- There is a distinction between a webpage and a website: a webpage is an individual page that forms part of a larger, broader website -- for example the Ask A Librarian page is a webpage within the Meriam Library's website.
- When citing content from the Web, cite the individual page where you found the information you are citing, not the broader website
- The title of a webpage is analogous to chapter or article title, and as such should be "put in quotation marks." The title of a website is analogous to a book or journal title, and as such should be italicised.
Rebecca MacKinnon, “Internet freedom is dead. Long live Internet freedom,” RConversation (blog), September 27, 2010,
- Section 14.243 of the Manual defines a blog as being a webpage with dated entries (posts) and dated comments
For additional information, see sections 14.243-246 of the Manual.