Last revised: November 2009
Citing Sources Using the Chicago Style Manual:
Author-Date (Parenthetical) System
Scope: This guide is designed to help researchers learn how to cite sources using the Chicago Style author-date system. This method of citation uses an in-text parenthetical system and is most common in the physical, natural, and social sciences. For more information, refer to The Chicago Manual of Style or Kate Turabian's Manual for Writers of Term Papers, Theses, and Dissertations.
TABLE OF CONTENTS
Quick Links to Sample Citations:
Overview of the Chicago/Turabian Documentation System
The Chicago system (also known as the Turabian system) allows for two different systems of documentation. The notes system is suggested for use in the humanities, art, and history, and uses footnotes (notes at the bottom of the page) to document sources. The in-text parenthetical system (known as the author-date system) is suggested for use in the physical, natural, and social sciences and uses endnotes (notes at the end of the paper on a separate sheet) to document sources.
This guide outlines the author-date system. For more information on using the notes system, see Citing Sources Using the Chicago Style Manual: Notes System.
What distinguishes the author-date system from the notes system is that the author-date system inserts minimal source information directly into the text itself, surrounded by parentheses, and follows up with the rest of the source information in a list of references at the end of the paper. Imagine that you're writing a paper on the ideal politician and are quoting a particular author's ideas about desirable qualities in a politician. An exerpt from a sentence in the text of a paper written using the author-date would look like this:
While some assert that the essential qualities a politician must possess are, "passion, a feeling of responsibility, and a sense of proportion" (Weber 1946, 33), others think that ...
The entry in the list of references would look like this:
Weber, Max. 1946. Politics as a Vocation. In Essays in Sociology, ed.
H.H. Garth and C. W. Mills, 26-45. New York: Macmillian.
Common Reference List Examples
This guide shows the most common sources appearing in research bibliographies. For more specific needs, see the The Chicago Manual of Style.
Books
Book by a single author
In the note, the author's name will appear in the usual order; in the bibliography it will be given with the last name first.
Bagby, John W. Cyberlaw Handbook for E-Commerce. New York: Harcourt
Brace, 2003.
Book with multiple authors
If the book has two or three authors, include all authors in the note and the bibliography. If the book has more than three authors, include all authors in the bibliography but only the first author followed by "and others" or "et al." in the note.
Smith, John, Janice Brown, Chris W. Enkunde, and Lois Denmark. The History
of the World Wide Web. 2nd ed. Chicago: University of Chicago Press,
2004.
Book with editors
Baumer, David L., Julius Poindexter, and Janice Brown, eds. Cyberlaw
and E-Commerce. Boston: McGraw Hill, 2002.
Chapter in an edited book
Heller, Chris, and Andrea Gottlieb. "Gender Roles in Ethiopian Culture." In
Gender in Cross-Cultural Perspective, edited by Sherry Collier, 45-56.
Louisville, KY: Pilgrim Press, 2001.
Periodicals
Journal article
Include the volume and issue number (if available). Give the range of page numbers on which the article appears in the bibliography and the specific page reference in the note (unless you are referring to the article as a whole).
James, Earl W.T., and Lucy Danker. "Obesity in American School Children: An
Epidemic." Journal of Nursing 389, no. 12 (2000): 399-405.
Journal article retrieved online
Include a URL for articles retrieved online or through an academic database such as EBSCOhost. Include page numbers for the print version if they are given.
Stem, Caroline J., James P. Lassoie, David R. Lee, and David J. Dessler.
"How 'Eco' is Ecotourism? A Comparative Case Study of Ecotourism in
Costa Rica." Journal of Sustainable Tourism 11, no. 4 (2003):
322-348. http://www.epnet.com/.
You do not need to include the access date unless your instructor requires it or the information is very time-sensitive. If you do to include the date, put it in parentheses at the end of the citation:
Stem, Caroline J., James P. Lassoie, David R. Lee, and David J. Dessler.
"How 'Eco' is Ecotourism? A Comparative Case Study of Ecotourism in
Costa Rica." Journal of Sustainable Tourism 11, no. 4
(2003): 322-348. http://www.epnet.com/ (accessed March 6, 2005).
Magazine article
Monthly magazines are usually cited by date only, even if volume and issue information is available.
Elliott, Michael. "Gypsy Foklore Revisited." Smithsonian, March
2004, 23-29.
For a magazine article accessed online, include the URL for the article or database from which it was retrieved. Again, volume and issue information is typically not included. Include the date the material was accessed only if your instructor requires it or the information is very time-sensitive.
Roman, Monica. "Son of Nafta?" Business Week, December 12, 2003.
http://www.epnet.com/.
Newspaper article
Chicago style recommends not including page numbers, as they may change between editions, though it may be helpful to include a section number or name and the particular edition consulted.
Edward Epstein, "It's That Time Again: Lawmakers Revisit Daylight Saving,"
San Francisco Chronicle, April 9, 2005, final edition.
If you access the article online through the newspaper's website, include the URL. If the URL for the specific article stops working, use the newspaper's homepage instead (e.g., http://www.nytimes.com/):
Lewin, Tamar, "College Enrollment Set Record in 2008," New York Times,
October 29, 2009. http://www.nytimes.com/2009/10/30/education/
30college.html.
If you access the article through an academic database, include the home URL for that database service:
Daniel Howden, "Polio at Mecca Sparks Fear for Muslim Thousands,"
Independent (London), February 12, 2005, first edition.
http://www.lexisnexis.com/.
Other Sources
Unpublished dissertation
Fitzpatrick, Kerry J. "Effects of Mowing on the Selection of Raptor Foraging
Habitat." PhD diss., University of Maryland, 2003.
Government document
This format may be used for reports, bulletins, circulars, and miscellaneous material issued by executive departments, bureaus, and agencies.
U.S. Department of Agriculture. Irrigation: A National Research Plan.
Washington, DC: GPO, 2001.
If the government document is accessed online, include the URL and date it was accessed:
U.S. Department of Justice. Bureau of Justice Statistics. Analysis of
Crime Patterns 1990-2000 by Shirley Marimer. Washington, DC: GPO, 2002.
http://www.usdoj.gov/346576/cr2002.pdf (accessed April 14, 2005).
Personal communication
Personal communication such as e-mails, telephone calls, or unpublished interviews are usually cited in the text or a note, but rarely appear in the bibliography. For example:
"In an e-mail message received by the author on December, 12, 2203, Sheila McCarthy stated that ..."
Website
Include as much of the following information as you can: author, title of the specific article, title of the site, sponsor of the site, and URL. Chicago style only recommends including the access date if the material is especially time-sensitive (or if your instructor requires it). If no author's name is given, use the sponsor of the site in the author's position.
Sullivan, Danny. "Boolean Searching." Search Engine Watch. http://www.searchenginewatch.com/facts/article/2155991.html.
Video
Videos are treated much like books, with the addition of the medium consulted (e.g., VHS, DVD).
Power! 1967-1968. VHS. Directed by Louis Massiah and Terry Kay
Rockefeller. Boston, MA: Public Broadcasting System Video, 1999.
For More Information
This guide is not a comprehensive list of all sources you may encounter. For more information and examples, refer to the Chicago Manual of Style:Gibaldi, Joseph. The Chicago Manual of Style. 15th ed.
Chicago: University of Chicago Press, 2003.
The Manual of Style is available at the McKeldin Reference Desk (Z253 .U69 2003) as well as several other campus libraries (check the catalog for availability), and may be purchased through the University Book Store or commercial vendors.
Turabian style, developed by Kate Turabian, is essentially similar to the Chicago style with slight modifications for the needs of student writers:Turabian, Kate L. A Manual for Writers of Term Papers, Theses, and
Dissertations. 7th ed. Chicago: University of Chicago Press, 2007.
It is also available through the University of Maryland Libraries (LB2369.T8 2007). Check the catalog for availability.
How to Construct an In-Text Parenthetical Reference
The author-date citation in the text must correspond exactly to its full citation in the reference list.
- Basic form. Include the author's last name and year of publication.
(Cox 1997)
(M. Cox 1997)
(Cox 1997, 21)
(Cox 1997a) and (Cox 1997b)
(Cox, Cunningham, and Hatleberg 1997)
(Cox et al. 1997)
(Cox 1997; Cunningham 1996; Hatleberg 1996)
Why Cite?
In researched writing, proper citation increases your credibility and allows readers to locate your sources; conversely, a failure to document your sources is plagiarism, a violation of the University of Maryland's Code of Academic Integrity with serious consequences.
Avoid plagiarism by gathering the information you need to create a citation when you first find each of your sources; don't wait until you begin writing the paper.
