List the names of all the authors of the reference the first time you cite the source if it has five or fewer authors. Use the first author's name followed by "et al." for sources with more than five authors. Connect the final two authors' names with the word "and" in the text or with an ampersand in a parenthetical citation; for example, "according to Smith, Jones, and Abner..." or "(Smith, Jones, & Abner...)."
Include the names of both authors each time a reference with two authors is mentioned. After the first mention of a study with three or more authors, use the first author's name followed by "et al." If two studies published in the same year have the same author listed first, list as many authors as necessary to differentiate between them each time you cite the source. Use "et al." after the final author listed this way, if necessary.
Add an author's first initial if you have references by different authors with the same last name. For example, include the initials for each citation of the reference if you have authors "A. Jones" and "B. Jones."
Cite "Anonymous" as the author if the author is anonymous. Use the title of the article if the author is unknown; include the entire title within the sentence or use the first few words of the title in a parenthetical reference. For example, use "How to Cite an APA Reference" in the sentence, but "("How to Cite"...)" in a parenthetical. Italicize or underline titles of books and reports and enclose titles of other references in quotation marks.
Add the year of publication for each citation. If the authors are listed within the text, place the year in parentheses immediately after the authors -- "Research by Smith (2000)." If the authors are included in parentheses, separate the authors and the year with a comma -- "(Smith, 2000)." Use the abbreviation "n.d." for undated sources.
Use the letters "a," "b" and so forth to distinguish between two or more references published in the same year that have same authors listed in the same order. For example, "Smith and Jones (2000a)" or "(Smith & Jones, 2000b)."
Include the page number for direct quotations. Use the abbreviation "p." for "page" or "pp." for "pages," or use "para." for "paragraph" if the reference is not paginated. Always add the page number after the quote; place it before the period but after the quotation mark for a short quotation and after the period for a block quotation. Include page numbers within a parenthetical reference -- "(Jones, 2000, p. 5)". If the authors are named in the text, the page number is in parentheses separate from the year -- "Jones (2000) says "this is..." (p. 5)."
Separate two or more references within the same parenthetical citation with a semicolon. For example, "(Jones, 2000; Smith, 2001)."