The Chicago Manual of Style: Author-Date

The Chicago Manual of Style has two styles: one that uses footnotes and endnotes and one that uses parenthetical citations. See our other Chicago Style handout if your discipline uses footnotes and endnotes.

The Chicago Manual of Style is a reference and style guide that uses the author-date system. It is most often used in the physical, natural, and social sciences.

For information on the citation format for sources not covered in this guide, refer to The Chicago Manual of Style, 16th ed.

Documenting sources

Sources must be documented in two places: in parenthetical references and in a reference list.

Two puzzle peices, labelled "in-text citations" and "reference entries", fit together to make a complete citation entry.

Parenthetical citations: Guidelines

Insert a citation when you use a direct quoteparaphrase information, or need to add further explanation to your text. Citations are placed in parentheses after a natural pause in meaning, but as close to the information as possible. Therefore, citations may appear in the middle of a sentence.

In-text citations tell readers exactly where you found specific information. Because they are meant to reflect the location of your evidence, they can contain the citation information for more than one source. See the final example in the sample below.

Sample paragraph

In the 1840s, a camera cost only $5, but developing images was prohibitively expensive, and only those above the middle class could participate in the hobby (Seiberling and Bloore 1965, 57). The financial constraints of daguerreotype photography forced all Canadian practitioners to engage with the medium as an occupation instead of as a hobby (Greenhill 1965, 22), and in spite of the high costs, many entrepreneurs saw photography as a potentially profitable endeavour. To offset the cost of production, Canadian daguerreotype photographers charged an exorbitant amount, typically ranging between $3 and $5 for one image, making it a luxury item only available to wealthy individuals such as John A. Macdonald or Louis Joseph Papineau, both of whom sat for portraits (Greenhill and Birrell 1979, 25; Skidmore 1996).

Reference list: Guidelines

The reference list is a list of all material you consulted for your project, even if you did not cite it in your text. Sources are listed alphabetically in a section titled “Reference List” that is placed at the very end of your assignment.

Remember that page numbers are not always necessary. For example, citations for ebooks generally do not require page numbers.

IMPORTANT NOTE: Chicago Author-Date uses hanging indents in the reference list which the following entries do not contain. They should be used as an example of the information to include in your reference list. For page formatting, see the sample reference list at the end of this resource.

Citation Format for Different Types of Sources


Type Citation Corresponding reference list entry
One Author

Format: (Last name Publication year, Page number)

Example: (Hawkins 2012, 12)

Last name, First name. Publication year. Title. City: Publisher.

Hawkins, Ty. 2012. Reading Vietnam Amid the War on Terror. New York: Palgrave Macmillan.

Multiple Authors

Format: (Last name and Last name Publication year, Page number)

Example: (Parker and Pollock 2013, 34)

Last name, First name and Last Name, First name. Publication year. Title. City: Publisher. 

Parker, Roziska and Griselda, Pollock. 2013. Old Mistresses: Women, Art and Ideology. New York: I.B. Tauris.

If a book has three or more authors, use the first author’s name and et al.

Sections within an edited collection

Format: (Last name Publication year, Page number)

Example: (Salahub 2012, 157)

Last name, First name. Publication year. "Title of Section." In Title of Book, edited by First name Last name, page range of section. City: Publisher.

Salahub, Jennifer. 2012. “Hannah Maynard: Crafting Professional Identity.” In Rethinking Professionalism Women and Art in Canada, 1850-1970, edited by Kristina Huneault and Janice Anderson, 135-67. Montréal: McGill-Queen’s University Press.

Periodicals and Journal Articles

Type Citation Corresponding reference list entry
Journals (Last name Publication year, Page)

(Tinkler 2008, 255)
Last name, First name. Publication year. “Article Title.” Journal Title volume number, issue number: page range.

Tinkler, Penny. 2008. “A Fragmented Picture:
Reflections on the Photographic Practices of Young People.” Visual Studies 23, no. 3: 255-66.
Electronic journals (Last name Publication year, Page)

(Cech and Waidzunas 2011, 21)
Last name First name. Publication year. "Article Title.” Journal Title volume number, issue number: page range. Accessed date. URL or DOI.

Cech, Erin A., and Tom J. Waidzunas. 2011. “Navigating the Heteronormativity of Engineering: The Experiences of Lesbian, Gay, and Bisexual Students.” Engineering Studies 3, no. 1: 1-24. Accessed March 15, 2015. doi:10.1080/19378629.2010.545065.


In the Chicago style, daily newspapers are not usually included in a bibliography. Instead, attribution may be given to information from a daily newspaper in footnotes or endnotes. Please refer to The Chicago Manual of Style 16th edition for more information.

Web Sources

Type Citation Corresponding reference list entry
Webpage with known Author and Date

(Last name, Year)

(Wilson, 2016)

Last name, First name. Year. "Webpage Title." Publisher or Website Name. Last modified date. URL.

Wilson, J. 2016. “Journey to Mars.” NASA. Last modified April 20.

Webpage with Unknown Author and Date

(“Webpage Title” Year)

(“Dogs of Canada” 2016)

Publisher or Website Name. Year. “Webpage Title.” Accessed date. URL.

Canadian Dog Association. 2016. “Dogs of Canada.” Accessed March 12.

Art and Photographs

Type Citation Corresponding reference list entry
Art and Photographs (Last name Publication year)

(Karsh 1962)
Last name, First name. Publication year. Title. Medium. dimensions. Repository, City. URL.

Karsh, Yousuf. 1962. Martin Luther King (1929-1968). Gelatin silver print. 49.6 x 40 cm. National Gallery of Canada, Ottawa.

Indirect Information

The use of a source that was found in another source is discouraged, but if the original source is absolutely unavailable, use “quoted in” to show where you found the information. In these cases, first provide the full citation information for the original source. Following “quoted in,” provide the full citation information for the secondary source using the appropriate source formatting (as detailed above).

Type Citation Corresponding reference list entry
Indirect information (Last name of original author Publication year of original source)

(Sontag 1977)
Last name, First name of original author. Publication year of original source. Title of Source. Publication City of Original Source: Publisher of Original Source. Quoted in…

Sontag, Susan. 1977. On Photography. New York: Farrar, Straus and Giroux. Quoted in Payne, Carol J. 2013. The Official Picture: The National Film Board of Canada’s Still Photography Division and the Image of Canada, 1941-1971. Ottawa: University of Ottawa Press

What to do when reference list information is missing:

  • Missing author: Cite by title
  • Missing publisher: Use n.p. in place of the publisher
  • Missing date: Use n.d. in place of the date
  • Missing place of publication: Use n.l. in place of the location

Sample Reference List

Please note that a reference list will always occur on its own page. Review a sample reference list (PDF).