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In-Text Citations: Author/Authors

Note: This page reflects APA 6, which is now out of date. It will remain online until 2021, but will not be updated. The equivalent APA 7 page can be found here.

APA style has a series of important rules on using author names as part of the author-date system. There are additional rules for citing indirect sources, electronic sources, and sources without page numbers.

Citing an Author or Authors

A Work by Two Authors: Name both authors in the signal phrase or in parentheses each time you cite the work. Use the word "and" between the authors' names within the text and use the ampersand in parentheses.

A Work by Three to Five Authors: List all the authors in the signal phrase or in parentheses the first time you cite the source. Use the word "and" between the authors' names within the text and use the ampersand in parentheses.

In subsequent citations, only use the first author's last name followed by "et al." in the signal phrase or in parentheses.

Six or More Authors: Use the first author's name followed by et al. in the signal phrase or in parentheses.

Unknown Author: If the work does not have an author, cite the source by its title in the signal phrase or use the first word or two in the parentheses. Titles of books and reports are italicized; titles of articles, chapters, and web pages are in quotation marks. APA style calls for capitalizing important words in titles when they are written in the text (but not when they are written in reference lists).

Note: In the rare case the "Anonymous" is used for the author, treat it as the author's name (Anonymous, 2001). In the reference list, use the name Anonymous as the author.

Organization as an Author: If the author is an organization or a government agency, mention the organization in the signal phrase or in the parenthetical citation the first time you cite the source.

If the organization has a well-known abbreviation, include the abbreviation in brackets the first time the source is cited and then use only the abbreviation in later citations.

Two or More Works in the Same Parentheses: When your parenthetical citation includes two or more works, order them the same way they appear in the reference list (viz., alphabetically), separated by a semi-colon.

Two or More Works by the Same Author in the Same Parentheses: When your parenthetical citation includes two or more works from the same author, list the years of publication in sequence, with the earliest first. Provide in-press citations last. Only list authors' surnames once for each list of dates. 

Following this pattern, multiple works from multiple authors can be contained within a single parenthetical. Separate authors' sources with a semicolon. Note, however, that the authors' names should be provided in the order they appear in the reference list regardless of when their sources were published.

Authors With the Same Last Name: To prevent confusion, use first initials with the last names.

Two or More Works by the Same Author in the Same Year: If you have two sources by the same author in the same year, use lower-case letters (a, b, c) with the year to order the entries in the reference list. Use the lower-case letters with the year in the in-text citation.

Introductions, Prefaces, Forewords, and Afterwords: When citing an Introduction, Preface, Foreword, or Afterword in-text, cite the appropriate author and year as usual.

Personal Communication: For interviews, letters, e-mails, and other person-to-person communication, cite the communicator's name, the fact that it was personal communication, and the date of the communication. Do not include personal communication in the reference list.

Citing Indirect Sources

If you use a source that was cited in another source, name the original source in your signal phrase. List the secondary source in your reference list and include the secondary source in the parentheses.

Note: When citing material in parentheses, set off the citation with a comma, as above. Also, try to locate the original material and cite the original source.

Electronic Sources

If possible, cite an electronic document the same as any other document by using the author-date style.

Unknown Author and Unknown Date: If no author or date is given, use the title in your signal phrase or the first word or two of the title in the parentheses and use the abbreviation "n.d." (for "no date").

Sources Without Page Numbers

When an electronic source lacks page numbers, you should try to include information that will help readers find the passage being cited. When an electronic document has numbered paragraphs, use the abbreviation "para." followed by the paragraph number (Hall, 2001, para. 5). If the paragraphs are not numbered and the document includes headings, provide the appropriate heading and specify the paragraph under that heading. Note that in some electronic sources, like webpages, people can use the "find" function in their browser to locate any passages you cite.

Note: Never use the page numbers of webpages you print out; different computers print webpages with different pagination.

Other Sources

The APA Publication Manual describes how to cite many different kinds of authors and content creators. However, you may occasionally encounter a source or author category that the manual does not describe, making the best way to proceed can be unclear.

In these cases, it's typically acceptable to apply the general principles of APA citation to the new kind of source in a way that's consistent and sensible. A good way to do this is to simply use the standard APA directions for a type of source that resembles the source you want to cite. For example, a sensible way to cite a virtual reality program would be to mimic the APA's guidelines for ordinary computer software.

You may also want to investigate whether a third-party organization has provided directions for how to cite this kind of source. For example, Norquest College provides guidelines for citing Indigenous Elders and Knowledge Keepers⁠—an author category that does not appear in the APA Manual. In cases like this, it's a good idea to ask your instructor or supervisor whether using third-party citation guidelines might present problems.