This page is brought to you by the OWL at Purdue (http://owl.english.purdue.edu/). When printing this page, you must include the entire legal notice at bottom.
From the OWL resource APA Formatting and Style Guide
Reference List: Author/Authors
The following rules for handling works by a single author or multiple authors apply to all APA-style references in your reference list, regardless of the type of work (book, article, electronic resource, etc.)
Single Author
Last name first, followed by author initials.
Berndt, T. J. (2002). Friendship quality and social development. Current Directions in Psychological Science, 11, 7-10.
Two Authors
List by their last names and initials. Use the ampersand instead of "and."
Wegener, D. T., & Petty, R. E. (1994). Mood management across affective states: The hedonic contingency hypothesis. Journal of Personality & Social Psychology, 66, 1034-1048.
Three to Six Authors
List by last names and initials; commas separate author names, while the last author name is preceded again by ampersand.
Kernis, M. H., Cornell, D. P., Sun, C. R., Berry, A., & Harlow, T. (1993). There's more to self-esteem than whether it is high or low: The importance of stability of self-esteem. Journal of Personality and Social Psychology, 65, 1190-1204.
More Than Six Authors
If there are more than six authors, list the first six as above and then "et al.," which stands for "and others." Remember not to place a period after "et" in "et al."
Harris, M., Karper, E., Stacks, G., Hoffman, D., DeNiro, R., Cruz, P., et al. (2001). Writing labs and the Hollywood connection. Journal of Film and Writing, 44(3), 213-245.
Organization as Author
American Psychological Association. (2003).
Unknown Author
Merriam-Webster's collegiate dictionary (10th ed.).(1993). Springfield, MA: Merriam-Webster.
NOTE: When your essay includes parenthetical citations of sources with no author named, use a shortened version of the source's title instead of an author's name. Use quotation marks and italics as appropriate. For example, parenthetical citations of the two sources above would appear as follows: (Merriam-Webster's, 1993) and ("New Drug," 1993).
Two or More Works by the Same Author
Use the author's name for all entries and list the entries by the year (earliest comes first).
Berndt, T.J. (1981).
Berndt, T.J. (1999).
When an author appears both as a sole author and, in another citation, as the first author of a group, list the one-author entries first.
Berndt, T. J. (1999). Friends' influence on students' adjustment to school. Educational Psychologist, 34, 15-28.
Berndt, T. J., & Keefe, K. (1995). Friends' influence on adolescents' adjustment to school. Child Development, 66, 1312-1329.
References that have the same first author and different second and/or third authors are arranged alphabetically by the last name of the second author, or the last name of the third if the first and second authors are the same.
Wegener, D. T., Kerr, N. L., Fleming, M. A., & Petty, R. E. (2000). Flexible corrections of juror judgments: Implications for jury instructions. Psychology, Public Policy, & Law, 6, 629-654.
Wegener, D. T., Petty, R. E., & Klein, D. J. (1994). Effects of mood on high elaboration attitude change: The mediating role of likelihood judgments. European Journal of Social Psychology, 24, 25-43.
Two or More Works by the Same Author in the Same Year
If you are using more than one reference by the same author (or the same group of authors listed in the same order) published in the same year, organize them in the reference list alphabetically by the title of the article or chapter. Then assign letter suffixes to the year. Refer to these sources in your essay as they appear in your reference list, e.g.: "Berdnt (1981a) makes similar claims..."
Berndt, T. J. (1981a). Age changes and changes over time in prosocial intentions and behavior between friends. Developmental Psychology, 17, 408-416.
Berndt, T. J. (1981b). Effects of friendship on prosocial intentions and behavior. Child Development, 52, 636-643.