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Chicago 17th edition author-date

Author-date for the Chicago Manual of Style 17th edition

About referencing

This referencing style guide provides a set of rules on how to acknowledge the thoughts, ideas and works of others when you use them in your own work.

Many types of publication examples have been provided in this guide. If you cannot find the example you need, you can:

  • consult The Chicago Manual of Style 17th edition.
  • view the reference lists of articles in publications that use Chicago style
  • consult the Instructions to authors, if writing for a journal
  • type the title of the item into Library Search to see if it has a suggested citation
  • adapt the rules of a similar publication type to the item
  • consult other institutions’ style guides
  • consult with your tutor or course coordinator.

Further resources

About Chicago 17th author-date

The Chicago Manual of Style allows for two different types of reference styles. There is the Notes and Bibliography Style, and the Author-Date System (a variation of the Harvard style).  This Guide is for the Author-Date system.

In this system, sources are briefly cited in the text, usually in parentheses, by author’s last name and year of publication. Each in-text citation matches up with an entry in a reference list, where full bibliographic information is provided.

An intext reference may look like (Blanshard 2006, 151) while its reference entry may look like:

Blanshard, Alastair. 2006. Hercules: A Heroic Life. London: Granta.

Any subsequent lines in a reference are on a hanging indent.  A hanging indent is an indent that indents all text except the first line.

Most of the recommendations in the notes and bibliographies version of Chicago 17th edition are identical for the author-date system.

Unlike notes and bibliography style, each entry in the reference list must correspond to a work cited in the text.

Punctuation marks and spaces within the citation are very important. Follow the punctuation and spacing as given in the examples.

Be careful where you input information into fields in the reference types in Endnote as the same information may need to be placed in different fields for different styles.  This is particularly relevant to inputting of dates.

Additional referencing information

Referencing specific formats

Suggestions for citing these formats, if there is not an existing rule in your referencing style:

  • ChatGPT and other Generative AI tools:
    • Check whether you are permitted to use ChatGPT or other Generative Artificial Intelligence (AI) tools prior to commencing your assignment.
    • If you use content from AI tools you must reference it or acknowledge it in accordance with course coordinator instructions or publisher policies.

What's New in Chicago 17 Author-Date

Amongst the changes and additions some of the more important include:

In journal citations, when the date of publication includes month and day, the year may be repeated to avoid ambiguity (15.14; 15.49; 15.50 etc).

Citing author-date sources by title when no author is credited (15.39).

Citing blog posts and blogs in author-date format (15.51).

For a full list see What’s New in the 17th Edition