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Citing Your Sources

Use these resources to aid in your citation writing process.

Chicago Style for the Sciences

Chicago Author-Date style may also be referred to as:

  • Author-Date System/Style
  • Parenthetical
  • Chicago Scientific

These are all the same thing!

Paraphrasing and In-Text Citations

Paraphrasing

Example:

Recent literature has examined long-run price drifts following initial public offerings and other factors (Ritter 1991).

When the author's name appears in the sentence, it does not need to be repeated in the citation.

Example:

Fisher (2009) reaches more or less the same conclusion.

In-Text Citations

Example:

Several studies have shown that "F. oxysporum isolates collected as nonpathogenic or pathogenic to other hosts that have very similar or identical elongation factor 1α and mitochondrial small subunit genotypes as banana pathogens were shown to cause little or no disease on banana" (O'Donnell 1998, 2044).

More than one author 
Example: 

(Smith and Johnson 1998, 14) 
(Smith, Johnson, and White 2001, 42)

More than three authors
Example: 
(Smith et al. 1998, 203)

No author
(Title Year, Page #)

Example: 
(Plagiarism and You 2002, 142) 
("Five Ways to Protect Yourself" 2000, 33)

Journal Articles

Journal article

Last name, first name. Year. "Article Title." Journal volume (issue, if available): pages. URL, if no DOI available. 

Example:

Novak, William J. 2008. "The Myth of the 'Weak' American State." American Historical Review 113:752-72. doi:10.1086/ahr.113.3.752

Journal article with multiple authors

Last name, first name, and First name Last name. Year. "Article Title." Journal volume (issue, if available): pages. URL, if no DOI available. 

Example:

Choi, Stephen J., and G. Mitu Gulati. 2008. "Bias in Judicial Citations: A Window into the Behavior of Judges?" Journal of Legal Studies 37 (January): 87-129. doi:10.1086/588263.

Include all authors, regardless of number, in the References List.

Books

Book

Last name, First name. Year. Title. Publisher's location: Publisher's name.

Example:

Pollan, Michael. 2006. The Omnivore’s Dilemma: A Natural History of Four Meals. New York: Penguin.

Books with multiple authors

Last name, First name, and First name Last name. Year. Title. Publisher's location: Publisher's name.

Example:

Heatherton, Joyce, James Fitzgilroy, and Jackson Hsu. 2008. Meteors and Mudslides: A Trip through the Earth. New York: Knopf. 

Include all authors, regardless of number, in the References List. Word oder and punctuation are the same as for two or three authors. 

Chapter in an Edited Book

Last name, First name of chapter author. Year. Chapter Title. In Book Title, edited by Editor, pages. Publisher's location: Publisher's name.

Example:

Gould, Glenn. 1984. "Streisand as Schwarzkopf." In the Glenn Gould Reader, edited by Tim Page, 308-11. New York: Vintage. 

Government reports

Government report

Last name, first name, First name Last name, and First name Last name. Year. Title. Report submitted to Department on date.

Example:

McKenna-Foster, Andrew, Lou Perrotti, and Elizabeth Sorrows. 2015. American Burying Beetle (Nicrophorus americanus) Survey on Nantucket Island, Massachusetts. Report submitted to the U.S. Fish and Wildlife Service on October 22, 2015.

Images

Online image

If there is no title, include a description of the image instead. 

Artist or creator. Year. "Title." Digital image. Website title. Access date, if no publication date available. URL. 

Example:

Ryder, Malcolm. 2006. “Driving Action with Values.” Digital image. Orchestra. Accessed April 11, 2017. http://www.malcolmryder.com/archives/2006/07/.

Newspaper Articles

Newspaper articles

It is usually sufficient to cite newspaper and magazine articles entirely within the text. If, for some reason, a reference list entry is needed, the year of publication is separated from the month and day. 

Last name, first name. Year. "Title." Newspaper, Month day, pages if available. URL if available. 

Example:

Carey, Benedict. 2008. "For the Brain, Remembering is like Reliving." New York Times, September 4. http://www.nytimes.com/2008/09/05/science/05brain.html. 

Pamphlets

Pamphlet

If no author is available, begin citation with title.

Last name, First name if available. Year. Title. Publisher's location: Publisher's name.

Example:

Lifestyles in Retirement, 1996. New York: TIAA-CREF. 

Theses or Dissertations

Thesis or dissertation

Titles of unpublished works appear in quotation marks, not italics. 

Last name, First name. Year. "Title." Thesis type, Academic institution. Database name, if available. URL, if available.

Example:

Choi, Mihwa. 2008. "Contesting Imaginaires in Death Rituals during the Northern Song Dynasty." PhD diss., University of Chicago. ProQuest Dissertations & Theses Global.

Vedrashko, Ilya. 2006. "Advertising in Computer Games," Msater's thesis, MIT. http://cms.mit.edu/research/theses/IlyaVedrashko2006.pdf. 

Websites

Websites

Organization or author name. Year. "Webpage title." Owner of webpage. Access date, if last modified date is not available. URL. 

Examples:

Microsoft Corporation. 2006. "WD2000: Visual Basic Macro to Assign Clipboard Text to a String Variable." Microsoft Help and Support. Last modified November 23, 2006. http://support.microsoft.com/kb/212730.

Evanston Public Library Board of Trustees. 2008. “Evanston Public Library Strategic Plan, 2000-2010: A Decade of Outreach.” Evanston Public Library. Accessed July 19, 2016. http://epl.org/library /strategic-plan-00.html. 

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