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Reference List: Author/Authors
Summary:
APA (American Psychological Association) style is most commonly used to cite sources within the social sciences. This resource, revised according to the 6th edition, second printing of the APA manual, offers examples for the general format of APA research papers, in-text citations, endnotes/footnotes, and the reference page. For more information, please consult the Publication Manual of the American Psychological Association, (6th ed., 2nd printing).
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 and Social Psychology, 66, 1034-1048.
Three to Seven 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., & Bach, J. S. (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 Seven Authors
List by last names and initials; commas separate author names. After the sixth author's name, use an ellipsis in place of the author names. Then provide the final author name. There should be no more than seven names.
Miller, F. H., Choi, M. J., Angeli, L. L., Harland, A. A., Stamos, J. A., Thomas, S. T., . . . Rubin, L. H. (2009). Web site usability for the blind and low-vision user. Technical Communication, 57, 323-335.
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 source above would appear as follows: (Merriam-Webster's, 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, and 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.
Introductions, Prefaces, Forewords, and Afterwords
Cite the publishing information about a book as usual, but cite Introduction, Preface, Foreword, or Afterword (whatever title is applicable) as the chapter of the book.
Funk, R., & Kolln, M. (1998). Introduction. In E. W. Ludlow (Ed.), Understanding English grammar (pp. 1-2). Needham, MA: Allyn and Bacon.
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APA Style
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APA Formatting and Style Guide
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- In-Text Citations: The Basics
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MLA Style
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MLA Formatting and Style Guide
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Preventing Plagiarism
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Contextualizing Plagiarism
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Avoiding Plagiarism
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Writing in the Engineering Classroom
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Professional, Technical Writing
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Writing in Literature
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Literary Theory and Schools of Criticism
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Writing in the Social Sciences
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Writing in Engineering
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INDOT Workshop Resources for Engineers
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Creative Writing
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Healthcare Writing
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Writing as a Veterinary Technician
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Writing in the Purdue SURF Program
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Professional, Technical Writing
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Job Search Writing
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Preparing an Application
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Job Search Letters
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Résumés and CVs
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Preparing an Application
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English as a Second Language
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ESL Students
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- Understanding Writing Assignments
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- Combining Sentences
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Prepositions
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- Punctuation
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