how to use a citation in an essay

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In-Text Citations: Author/Authors

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Though the APA's author-date system for citations is fairly straightforward, author categories can vary significantly from the standard "one author, one source" configuration. There are also additional rules for citing authors of indirect sources, electronic sources, and sources without page numbers.

A Work by One Author 

The APA manual recommends the use of the author-date citation structure for in-text citation references. This structure requires that any in-text citation (i.e., within the body of the text) be accompanied by a corresponding reference list entry. In the in-text citation provide the surname of the author but do not include suffixes such as "Jr.". 

Citing Non-Standard Author Categories

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 or More Authors

List only the first author’s name followed by “et al.” in every citation, even the first, unless doing so would create ambiguity between different sources.

In  et al. , et  should not be followed by a period. Only "al" should be followed by a period.

If you’re citing multiple works with similar groups of authors, and the shortened “et al” citation form of each source would be the same, you’ll need to avoid ambiguity by writing out more names. If you cited works with these authors:

They would be cited in-text as follows to avoid ambiguity:

Since et al. is plural, it should always be a substitute for more than one name. In the case that et al. would stand in for just one author, write the author’s name instead.

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 that "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, just as you would an individual person.

If the organization has a well-known abbreviation, you may include the abbreviation in brackets the first time the source is cited and then use only the abbreviation in later citations. However, if you cite work from multiple organizations whose abbreviations are the same, do not use abbreviations (to avoid ambiguity).

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.

If you cite multiple works by the same author in the same parenthetical citation, give the author’s name only once and follow with dates. No date citations go first, then years, then in-press citations.

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.

If using a footnote to reference personal communication, handle citations the same way.

Traditional Knowledge of Indigenous Peoples

When citing information you learned from a conversation with an Indigenous person who was not your research participant, use a variation of the personal communication citation above. Include the person’s full name, nation or Indigenous group, location, and any other relevant details before the “personal communication, date” part of the citation.

Citing Indirect Sources

Generally, writers should endeavor to read primary sources (original sources) and cite those rather than secondary sources (works that report on original sources). Sometimes, however, this is impossible. 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. If you know the year of the original source, include it in the citation.

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. Use the heading or section name, an abbreviated heading or section name, a paragraph number (para. 1), or a combination of these.

Note:  Never use the page numbers of webpages you print out; different computers print webpages with different pagination. Do not use Kindle location numbers; instead, use the page number (available in many Kindle books) or the method above. 

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 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 computer software.

You may also want to investigate whether a third-party organization has provided directions for how to cite this kind of source.