• 4-minute read
• 8th October 2018

A Guide to Chicago Author–Date Citations

The Chicago Manual of Style sets out two approaches to referencing sources in academic writing, one of which uses parenthetical citations. And while the basic in-text citation format is easy to grasp, it varies in many situations.

In this post, then, we’re looking at how to make sure your referencing is always error free when using Chicago author–date citations.

1. Basic Chicago Author–Date Citations

Chicago author–date citations require giving the surname of the author and the year of publication for a source in round brackets. This is usually at the end of the relevant clause. For example:

There are many approaches to referencing (Fry 2001).

If the author is already named in the text, you do not need to repeat it in the citation. Instead, simply cite the year of publication immediately after the author is named:

Fry (2001) says that there are many approaches to referencing.

2. Citing a Work with Two or More Authors

To reference a source with two authors using Chicago author–date citations, simply give both names in the order they are listed on the book, joined with the word “and” (not “&”):

Two is the best number (Fry and Smith 1998).

For a source with three authors, use a serial comma before the last name:

Three is still a good number (Fry, Smith, and Connor 2011).

If a source has four or more authors, cite the first name followed by “et al.”:

It turns out that four is too many (Fry et al. 2017).

You should, however, name all of the authors in the reference list at the end of your document.

3. Quoting Sources

To quote a source with Chicago referencing, give the page number(s) in the citation after a comma:

He said it “exactly like this” (Smith 1984, 23).

Fry (2001, 12-13) argues that “eyewitness accounts are unreliable.”

The first citation above shows us that the quote comes from page 23 of the source in question. The second shows us that the quote comes from pages 12-13 of the source cited.

4. Two Works by the Same Author from the Same Year

If you cite two sources written by the same author in the same year, a year of publication alone won’t be enough to show which source you’re citing.

In this situation, you should also add a letter after the year for each source that you cite in your work. For example, in the reference list, sources by the same author should be ordered alphabetically by title. If they are also from the same year, you will add “a” after the first, “b” after the second, etc.

Fry, John. 1990a. Déjà Vu and You. New York: Simon & Schuster.

———. 1990b. False Recollections. New York: Penguin Press.

To show which source is which in citations, simply include the correct letter:

Fry (1990a) originally worked on déjà vu. But he later examined the sense of having already lived through a present moment (Fry 1990b).

In the passage above, for instance, we cite two sources by “Fry” from the year 1990. We have therefore added the letters “a” and “b” to show that they are distinct texts.

5. Two Authors with the Same Surname

To cite two authors with the same name, include first initials in citations:

The Earth revolves around the Sun (J. Smith 2004). However, people once believed that the Sun revolved around the Earth (R. Smith 1992).

You should list the authors with first names in full in the reference list, however, just like you would with any other author.

6. Citing More than One Source at Once

You can also cite more than one source in a single citation. To cite two or more sources by a single author at once, for example, you can simply add a comma between the years of publication:

Studies have shown that the Earth is round (Smith 1971, 1982, 2006).

Here, for instance, we’ve cited three sources by “Smith” all at once. You can also cite more two or more sources by different authors. To do this, use a semicolon between each author’s surname:

Some people still believe in a flat Earth (Fry 2015; Smith 2006).

Names in a citation can be ordered alphabetically, chronologically, or by importance. It is simply a matter of clarity and preference. Here, we’ve ordered them alphabetically.