Chicago Style

This page introduces the basics of Chicago style. For more detailed guidelines and advanced formatting help, consult The Chicago Manual of Style, 17th edition. The full text is available at the editors’ Web site, along with the abridged Chicago Style Quick Guide.

The Chicago Manual of Style (CMS) uses two systems of documentation: a note-bibliography system and an author-date system. Used most often in literature, history, and the arts, the note-bibliography system includes bibliographic information in notes, supplemented by a bibliography. The author-date system includes citation in parentheses (author, publication date, and page number if necessary), and full publication information is included in a bibliography. This system is used most often in the physical, natural, and social sciences.

Bibliographic Notes and In-Text Citations

Note-Bibliographic System

In the note-bibliography system, you cite a source by inserting a superscript number in the text and listing the source’s essential bibliographic information in either a footnote or an endnote. The source’s full bibliographic entry is included on a list at the end. To determine whether you should use footnotes or endnotes, consult your instructor. If you have to decide which type of note to use, see CMS 14.43-14.45.

In the note-bibliography system, notes contain full bibliographic information or a shortened version. For many university papers, professors require a full bibliographic note when you cite a work the first time and a shortened note for subsequent citations. Each source has a full entry in the bibliography. CMS states that you may use a shortened citation for all notes, since the full publication information is available in the bibliography. Be sure to read your assignment. Shortened citations include the last name of the author and the key word or words (no more than four) of the title of the work, as well as the page numbers. Superscript numbers are placed at the end of a sentence or clause, and after any marks of punctuation (except the dash).

Full citation in a note:

1. Newton N. Minow and Craig L. LaMay, Inside the Presidential Debates: Their Improbable Past and Promising Future (Chicago: University of Chicago Press, 2008), 24-25.

Shortened citation in a note:

1. Minow and LaMay, Presidential Debates, 24-25.

If you are citing a long electronic source or a long work with no page numbers, your note should include a chapter number, a paragraph number, or a section heading to help your reader locate a particular passage. For shorter works, a locator may be unnecessary. (CMS 14.17) For more examples of notes, see the table of bibliographic forms at the end of this handout. (CMS 14.14-15, 14.21, 14.24-28)

Previous editions of Chicago Manual of Style encouraged the use of “ibid” for successive references to the same work, but this practice is now discouraged in favor of shortened notes. This is primarily to adjust to the rise in electronic formats that link to one note at a time, as “Ibid” risks confusing a reader and forces them to hunt for the prior citation. However, instead of repeating the full shortened citation, the title of the work may be omitted. (CMS 14.34)

Instead of:

    1. Morrison, Beloved, 3.
    2. Ibid., 18.

Chicago now encourages:

    1. Morrison, Beloved, 3.
    2. Morrison, 18.

Author-Date System

 For the author-date system, parenthetical citations contain the author’s last name, the publication date of the work cited, and a page number if needed. If the author’s name appears in the text of your sentence, the citation contains only the publication date and a page number if needed. (CMS 15.5, 15.20-30).

In-text citation:

Abramowitz and Saunders (2005) suggest that the mass public is deeply divided between red states and blue states and between churchgoers and secular voters.

Cells grown from Henrietta Lacks’s tumor helped scientists to discover how many chromosomes are in a normal human cell (Skloot 2010, 100).

If you cannot find an author for your source, include a shortened version of the title for the in-text citation and the bibliographic entry. If you cannot find a date of publication for your source, use an access date for the in-text citation and the bibliographic entry. CMS suggests that the owner or publisher of a website may be used in place of the author’s name. (CMS 15.32, 15.51)

In-text citation:

Besides the University of Arkansas Razorbacks, no other American sports team uses a pig or a hog as its mascot (Wikipedia 2011).

Reference List Entry 

Wikipedia. 2011. “Arkansas Razorbacks.” Accessed January 27.

Quoting from Sources

Note-Bibliography System

For the note-bibliography system, the note should be placed after a quotation and after any punctuation marks at the end of the quotation. (CMS 14.21)

As Edward Tufte points out, “A graphical element may carry date information and also perform a design function usually left to non-data-ink.”⁶

Author-Date System

For the author-date system, the citation of the source normally follows a direct quotation, but the CMS states that it can also precede the quotation – particularly if such a placement allows the date to appear with the author’s name. (CMS 15.25)

As Edward Tufte points out, “A graphical element may carry date information and also perform a design function usually left to non-data-ink” (2001, 139).

As Edward Tufte (2001, 139) points out, “A graphical element may carry date information and also perform a design function usually left to non-data-ink.”

When the source of a block quotation is given in parentheses at the end of the quotation, the citation follows the final punctuation mark of the quoted material. (CMS 15.25)

The 2007 Pew Global Attitudes Survey showed a remarkable increase worldwide in positive views about free trade, markets, and democracy. Large majorities in countries from China and Germany to Bangladesh and Nigeria said that growing trade ties between countries were good. Of the forty- seven countries polled, however, the one that came in dead last in terms of support for free trade was the United States. (Zakaria 2009, 418)

Types of Bibliographies

Chicago style recognizes several different types of bibliographies, but the two most commonly used are the full bibliography and the selected bibliography. Many university papers require a full bibliography, which includes all works cited in the paper. A selected bibliography contains full publication information for only some of the works cited and includes a headnote explaining selections. If your instructor asks for a selected bibliography, consult the CMS. (CMS 14.14, 14.59) 

For the note-bibliography system, the CMS recommends the full bibliography, most often titled “Bibliography” and less frequently “Works Cited” or “Literature Cited.”

The author-date system always uses the full bibliography; thus, each entry in the reference list must correspond to a work cited in the text. This bibliography page is usually titled “References” or “Works Cited.” (CMS 15.5)

For both types, entries are arranged alphabetically by authors’ last names. If the source has no author, list by editor, translator, compiler, or title. Both types of bibliographies also are in flush-and-hang style, or hanging-indention format: the first line of the entry is flush left, with subsequent lines indented. (CMS 1.61, 14.57)

The major difference between the two systems is that the bibliography for the author-date system places the year of publication immediately after the author’s name. (CMS 15.5). 

Bibliographic entry for the note-bibliography system:

Skloot, Rebecca. The Immortal Life of Henrietta Lacks. New York: Crown Publishers, 2010.

Bibliographic entry for the author-date system:

Skloot, Rebecca. 2010. The Immortal Life of Henrietta Lacks. New York: Crown Publishers.

Citation examples of several common source types in both systems

Source Type Note-Bibliography System Author-Date System Bibliography Entry
Book with one author (CMS 14.75) 1. Michael Pollan, The Omnivore's Dilemma: A Natural History of Four Meals (New York: Penguin, 2006), 99-100 (Pollan 2006, 99-100) Pollan, Michael. The Omnivore's Dilemma: A Natural History of Four Meals. New York: Penguin, 2006.
Book with editor, translator, or compiler instead of author (CMS 14.87, 15.35) 1. Richmond Lattimore, trans. The Iliad of Homer (Chicago: University of Chicago Press, 1951), 91-92. (Lattimore 1951, 91-92) Lattimore, Richmond, trans. The Iliad of HomerChicago: University of Chicago Press, 1951.
Book with editor, translator, or compiler in addition to author (CMS 14.88)  1. Gabriel García Márquez, Love in the Time of Cholera, trans. Edith Grossman (London: Cape, 1988), 242-55. (García Márquez 1988, 33) García Márquez, Gabriel, Love in the Time of Cholera. Translated by Edith Grossman. London: Cape, 1988.
Book with two or three authors or editors (CMS 14.76)  1. Geoffrey C. Ward and Ken Burns, The War: An Intimate History, 1941-1945 (New York: Knopf, 2007), 52. (Ward and Burns 2007, 52)  Ward, Geoffrey C., and Ken Burns. The War: An Intimate History, 1941-1945. New York: Knopf, 2007.
Source with more than three authors or editors (CMS 14.76)  1. Jing Chen et al., "Effects of Computer Versus Paper Administration of an Adult Functional Writing Assessment," Assessing Writing 16, no. 1 (2011): 65. (Chen et al. 2011, 65) Chen, Jing, Sheida white, Michael McCloskey, Jaleh Soroui, and Young Chun. "Effects of Computer Versus Paper Administration of an Adult Functional Writing Assessment." Assessing Writing 16, no. 1 (2011): 49-71.
Chapter in a book (CMS 14.111) 1. John D. Kelly, "Seeing Red: Mao Fetishism, Pax Americana, and the Moral Economy of War," in Anthropology and Glocal Counterinsurgency, ed. John D. Kelly et al. (Chicago: University of Chicago Press, 2010), 77. (Kelly 2010, 77) Kelly, John D. "Seeing Red: Mao Fetishism, Pax Americana, and the Moral Economy of War." In Anthropology and Glocal Counterinsurgency, edited by John D. Kelly, Beatrice Jauregui, Sean T. Mitchell, and Jeremy Walton, 67-83. Chicago: University of Chicago Press, 2010.
Article in a print journal with volume number only (CMS 14.180) 1. Joshua I. Weinstein, "The Market in Plato's Republic," Classical Philosophy 104 (2009): 440. (Weinstein 2009, 440) Weinstein, Joshua I. "The Market in Plato's Republic." Classical Philosophy 104 (2009): 439-58.
Aricle in a print journal with volume and issue numbers (CMS 14.180, 15.46) 1. Cecelia Menjívar, "Liminal Legality: Salvadoran and Guatemalan Immigrants' Lives in the United States," American Journal of Sociology 111, no. 4 (2006): 1028. (Menjívar 2006, 1028) Menjívar, Cecelia. "Liminal Legality: Salvadoran and Guatemalan Immigrants' Lives in the United States." American Journal of Sociology 111, no. 4 (2006): 99-1037.
Article in a scholarly journal accessed electronically (CMS 14.180, 14.184) 1. Gueorgi Kossinets and Duncan J. Watts, "Origins of Homophily in an Evolving Social Network," American Journal of Sociology 115 (2009): 411, accessed February 28, 2010, doi:10.1086/599247. (Kossinets and Watts 2009, 411) Kossinets, Gueorgi, and Duncan J. Watts. "Origins of Homophily in an Evolving Social Network." American Journal of Sociology 115 (2009): 405-50. Accessed February 28, 2010. doi:10.1086/599247.

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