How to Cite Different Groups of Authors With the Same Lead Author and Publication Date

 

 

by Tyler Krupa

What’s in a name? Properly citing different groups of authors with the same lead author and publication date can make a big difference. When you have two or more references of more than three surnames with the same year and they shorten to the same form (e.g., both Smith, Jones, Young, Brown, & Stanley, 2001, and Smith, Jones, Ward, Lee, & Stanley, 2001, shorten to Smith et al., 2001), clarify which one you are citing each time. On the second and all subsequent citations, cite the surnames of the first two authors and of as many of the next authors as necessary to distinguish the two references, followed by a comma and et al. (see the sixth edition of the Publication Manual, p. 175).

Smith, Jones, Young, et al., 2001 Smith, Jones, Ward, et al., 2001

Are you tempted to use an a or b to designate which is which? This is a common error—placing lowercase letters (a, b, c, etc.) after the publication date instead of citing the necessary surnames. Lowercase letters are used after the publication date only for references with the same author (or with the same two or more authors in the same order) with the same publication date (in which case the references are arranged alphabetically by title; see p. 182 in the Publication Manual). So, using a or b is not appropriate when you have different groups of authors with the same lead author and publication date. Here are some examples that show the correct and incorrect ways to format these types of references in your reference list and in your text citations:

Correct: McGregor, I., Nash, K., Mann, N., & Phills, C. E. (2010). Anxious uncertainty and reactive approach motivation (RAM). Journal of Personality and Social Psychology, 99, 133–147. doi:10.1037/a0019701 McGregor, I., Nash, K., & Prentice, M. (2010). Reactive approach motivation (RAM) for religion. Journal of Personality and Social Psychology, 99, 148–161. doi:10.1037/a0019702 Incorrect: McGregor, I., Nash, K., Mann, N., & Phills, C. E. (2010a). Anxious uncertainty and reactive approach motivation (RAM). Journal of Personality and Social Psychology, 99, 133–147. doi:10.1037/a0019701 McGregor, I., Nash, K., & Prentice, M. (2010b). Reactive approach motivation (RAM) for religion. Journal of Personality and Social Psychology, 99, 148–161. doi:10.1037/a0019702

In the examples above, the authors are not the same, and therefore a and b should not be used after the publication date.

When citing these references in the text, cite the necessary number of surnames to distinguish between the references. In these two references, this distinction is not reached until the third author. Here’s how these reference should be cited in text:

Correct: First citations: (McGregor, Nash, Mann, & Phills, 2010) (McGregor, Nash, & Prentice, 2010) Second and subsequent citations: (McGregor, Nash, Mann, & Phills, 2010) (McGregor, Nash, & Prentice, 2010) Incorrect: First citations: (McGregor, Nash, Mann, & Phills, 2010a) (McGregor, Nash, & Prentice, 2010b) Second and subsequent citations: (McGregor et al., 2010a) (McGregor et al., 2010b)

Note that in the first reference example above, you should use the four surnames “McGregor, Nash, Mann, and Phills” instead of “McGregor, Nash, Mann, et al.” in the second and subsequent citations. The reason for this is that et al. means “and others,” so if there is just one more surname remaining after distinguishing between the two references, just list the final name instead of using et al. (For more examples on how to correctly use et al., see a recent post to our blog.)

Now you know how to properly cite different groups of authors with the same lead author and publication date. Questions? Leave us a comment.