Using the Chicago reference style

This page provides information from the NTNU University Library to help you when you need to use the Chicago style.

All examples on this page are based on version 16 of Chicago. The newest available version is 17, be aware that differences between the two may occur.

Norsk versjon: Bruke referansestilen Chicago

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Chicago style

Here, Chicago B is used, i.e. the author-date version of Chicago (Chicago A is a note style). Check which reference style your department recommends before you begin writing your paper.

The Chicago style is commonly used in the social sciences, arts and humanities.

Other styles

  • APA style is used in the social sciences, arts and humanities.
  • Harvard style is used in the social sciences, technology and natural sciences.
  • Vancouver style is used in medicine and the natural sciences, and sometimes in technology.

Examples of using the Chicago style in a reference list


The examples show how to write references in-text and in reference lists based on what kind of source you are citing.

Reference list in Chicago style

When writing a reference list in the Chicago style:

  • Sort the list alphabetically by author’s surname.
  • Include all citations in one list (not divided up into books, articles, websites, etc.)
  • Start the reference list on a new page. Use “Reference list” or “Literature list” as the heading.
  • If there are 4 authors or more, only write the first author’s surname along with “et al.” when referencing in-text (e.g. Cheng et al.). In the literature list, include all authors.
  • Use italics for
    • Titles of journals and volumes
    • Book titles
  • With secondary references, include both sources in the reference list.

Personal communication in Chicago style

In the Chicago style, personal communications should not be included in the reference list, if the information is not recoverable. Personal communications are conversations, emails, phone calls, etc. Remember to ask for permission from the communicator before citing him/her. You can cite personal communications in the text. You should include the name and title of your conversation partner, the date of communication and the context in which the communication took place.

The Chicago style in-text

When using the Chicago style in-text:

  • When there are four or more authors, write only the first author’s surname followed by “et al.” when referencing in-text (e.g. Cheng et al.) (in the literature list, write the names of all authors)
  • When using secondary references, name both sources in-text: Johnson and Peters’ studies (1939, cited in Wagner 1982, 207)
  • To distinguish multiple publications by the same author published the same year, write a, b, c, etc. after the year: Hansen (1988a) and Hansen (1988b)
  • When a work has no identifiable author, write the title.
  • Publications with many authors who are cited more than once
    • 2 or 3 authors: write both authors’ names every time you cite them. Example: (Furseth and Everett 1997), (Reve, Lensberg and Grønhaug 1992)
    • 4 or more authors: only write the surname of the first author followed by et al. Example: Cheng et al. (2004) Note that all authors’ names should be in the reference list.
  • Use page numbers when:
    • if you use ideas from a specific page/specific pages in a work


Example: Researchers such as Warwick (1992), Alt and King (1994) and Warwick and Easton (1992) found that…


Citations should be clearly marked in the text. Short citations should be integrated in-text and marked with quotation marks. Citations longer than one sentence should be in a separate indented paragraph, without quotation marks. The name of the author, year of publication and page number are written in brackets following the citation.


  • Short citation: “Sitering vil si ordrett gjengivelse av andres arbeider.” (Stene, 1999, 125).
  • The name of the author is integrated in the paragraph: Stene (1999) defines citation as: “Sitering vil si ordrett gjengivelse av andres arbeider. Da skal det være ordrett, og ikke misbrukt i forhold til den sammenhengen sitatet brukes i” (125).
  • Source with 2-3 authors: "Ved direkte sitater skal henvisningen gi informasjon om forfatter, årstall og sidetall" (Furseth and Everett 1997, 141).
  • Source with 4 or more authors: (Wakefield et al. 1998).

Indirect citation - Paraphrases

A paraphrase is a reformulation of the original text.

Example: Furseth and Everett (1997) maintain that the primary reason behind use of references and bibliographies is the ideal of research as a collective endeavour. Research should be verifiable, and those reading your work should be able to find those sources your material is based upon (142).

More on the Chicago style

Information on how you write references in-text and in a reference list with the Chicago style is gathered from the Chicago Manual of Style. They also have their own website:

University of Chicago Press Staf, ed. 2010. The Chicago Manual of Style. 16th ed. Chicago: University of Chicago Press.


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