Author–Date Citation System

Use the author–date citation system to cite references in the text in APA Style. In this system, each work used in a paper has two parts: an in-text citation and a corresponding reference list entry.

• In parenthetical citations, use an ampersand (&) between names for a work with two authors or before the last author when all names must be included to avoid ambiguity.
• In narrative citations, always spell out the word “and.”

Learn more

The author–date citation system is covered in Sections 8.10–8.36 of the APA Publication Manual, Seventh Edition

This guidance has been revised from the 6th edition.

Number of authors to include in in-text citations

The format of the author element of the in-text citation changes depending on the number of authors and is abbreviated in some cases.

• For a work with one or two authors, include the author name(s) in every citation.
• For a work with three or more authors, include the name of only the first author plus “et al.” in every citation (even the first citation).

The following table shows the basic in-text citation styles:

(Salas & D’Agostino, 2020)

Salas and D’Agostino (2020)

Three or more authors

(Martin et al., 2020)

Martin et al. (2020)

Group author with abbreviation

First citation a

(National Institute of Mental Health [NIMH], 2020)

National Institute of Mental Health (NIMH, 2020)

Group author without abbreviation

(Stanford University, 2020)

Stanford University (2020)

a Define the abbreviation for a group author only once in the text, choosing either the parenthetical or the narrative format. Thereafter, use the abbreviation for all mentions of the group in the text.

Exceptions to the basic in-text citation styles

• when two works in a paper would both abbreviate to the same “et al.” form (spell out as many surnames as needed to disambiguate)
• when multiple works in a paper have an identical author (or authors) and publication year (append letters to the years)
• when the first authors of multiple references in a paper share the same surname but have different initials (use initials in the in-text citations)

Dates in a citation

• The year in the in-text citation should match the year in the reference list entry.
• Use only the year in the in-text citation, even if the reference list entry contains a more specific date (e.g., year, month, and day).
• For works with no date, use “n.d.” in the in-text citation.
• For works that have been accepted for publication but have not yet been published, use “in press.”

Repeating a citation

When repeating a citation, show the entire citation; do not, for example, include only a page number (the abbreviation “ibid.” is not used in APA Style). Instead, use the following guidelines:

• Include the author(s) and year for every parenthetical in-text citation.
• Do not repeat the year for narrative in-text citations the second and subsequent times they appear in a single paragraph. Follow this guideline with each new paragraph (i.e., include the year in the first narrative citation in a new paragraph).
• However, if you cite multiple works by the same author or authors, regardless of the publication years, include the date in every in-text citation to prevent ambiguity. For example, if you cite Mohammed and Mahfouz (2017) and Mohammed and Mahfouz (2019), include the year with every citation, even when one of the references is cited multiple times in a single paragraph.

Further guidelines for in-text citations

• Each in-text citation must correspond to only one reference list entry.
• Do not include suffixes such as “Jr.” in the in-text citation.
• For works with an unknown author (see Section 9.12), include the title and year of publication in the in-text citation.
• Chapter 10 of the Publication Manual (7th ed.) includes more than 100 reference examples, each of which includes examples of the parenthetical and narrative citations.
• For more guidance and examples, see the Publication Manual.