When quoting an entire source, only the author and year of publication are required. However, when using a direct quote from a source, the author, year and page number(s) are required for the citation. In both citations the author name may be included in the text or in the parenthetical reference. For sources such as websites and e-books that have no page numbers, use a paragraph number. More information on citing sources without pagination is given on the APA Style web page.
APA Manual pp. 169-179, Section 6.01-6.21
Two Authors:
When a work has two authors, both names should be cited every time the reference occurs in the text.
Example: Tyler and Simpson (2008) investigated...
Three to Five Authors:
When you cite a work with three to five authors, cite all of the authors' last names the first time the reference is used. Subsequent citations for the reference can requires only the first author's last name be used follwed by et. al.
Example: Woodbank, Tyler, Joseph, and Simpson (2010) report that...
Woodbank et al. (2010) found...
Six or More Authors:
When a reference has six or more authors, cite only the last name of the first author followed by et al.
Example: Tyler et al. (2009)...
APA Manual pp. 177-178, Section 6.12
If you cite multiple works by different authors in one parenthetical reference, cite each work in parentheses as you normally would, place in alpahabetical order and use semicolons to separate the citations.
Example: Several studies (Miller, 1999; Shafranske & Mahoney, 1998)...
Two or more works by the same author should be arranged by year.
Example: Past research (Gogel, 1990, 2006)...
Works written by the same author(s) and published in the same year should include a suffix, a, b, c, etc., added after the year.
Example: Several studies (Derryberry & Reed, 2005a, 2005b; Rothbart, 2003a, 2003b)...
APA Manual pp. 177-178, Section 6.16
Cite web pages in text as you would any other source, using the author and date if known. If the author is not known, use the title and the date as the in-text citation (for long titles just use the first few words). Your in-text citation should lead your reader to the corresponding entry in the reference list. For sources with no date use n.d. (for no date) in place of the year: (Hanson, n.d.).
Examples:
Web page with author:
Role-play can help children learn techniques for coping with bullying (Kraiser, 2011).
Web page with no author:
Voting rights were limited until the year 1927 ("Voting," 2017).
Web page with no date:
Establishing regular routines, such as exercise, can help survivors of disasters recover from trauma (American Psychological Association [APA], n.d.).
When using parenthetical documentation for in-text citations, remember that sources cited in the text must point to specific sources on the References page.
When citing sources by different authors who have the same last name, include the author's first initials in all in-text citations.
Example: Among studies we review M. A. Light (2008) and I. Light (2006).
APA Manual p. 176, Section 6.14
When citing a Twitter or Facebook feed as a whole or to discuss it in general, it is sufficient to give the site URL in-text, inside parentheses. There is no need for a reference list entry.
Example: President Obama uses Twitter (http://www.twitter.com/barackobama) and Facebook (http://www.facebook.com/barackobama) to keep citizens up to speed on his initiatives, especially health care reform and Supreme Court nominations.
When citing specific Twitter posts and Facebook updates, citations should be included on the References list*. Corresponding in-text citations should follow the (Author, Year) example.
Example: President Obama announced the launch of the American Graduation Initiative (BarackObama, 2009a). He also stated that he was “humbled” to have received the Nobel Peace Prize (Barack Obama, 2009b).
*See Reference Examples for how to cite a Twitter post or Facebook update.
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