When to Cite in an APA-Style Paper

I often receive the question, “How many sources do I need in my APA paper’s text or reference list?” There is no definitive answer to this question, since the number of in-text citations and sources on a reference list depend on an individual author’s work.

The best response to this question can be found in the American Psychological Association’s publication manual (APA, 2010), which has provided the following guidance. Words inside brackets are authored by me:

When to Cite

Cite the work of those individuals whose ideas, theories, or research have directly influenced your work. They may provide key background information, support or dispute your thesis, or offer critical definitions of data. Citation of an article implies that you have personally read the cited work [see Note 1]. In addition to crediting the ideas of others that you used to build your thesis, provide documentation for all facts and figures that are not common knowledge [see Note 2].

The number of sources you cite in your work will vary by the intent of the article [or paper, as in a college course]. For most articles [or papers], aim to cite one or two of the most representative sources for each key point [see Note 3]. (p. 169)

The following figure provides an example of citation levels, based on an actual APA-style paper (click the image to enlarge the figure):

NOTE: Adapted from “Publication manual of the American Psychological Association (6^th ed.),” by American Psychological Association, 2010, p. 170. Copyright 2010 by the American Psychological Association, Washington, DC.

NOTE 1: When citing sources, cite the original or primary source of the work. See Tip 24 in my APA citation and writing Wiki. For example, if you wish to cite Peter G. Northouse’s introduction to leadership, you would read his original work (e.g., Introduction to Leadership: Concepts and Practice, 2^nd ed., 2012) before you quote or attribute and cite his work. The APA publication manual discourages citation of secondary sources. For example, Northouse (2012, p. 19) used a quote and citation from another author to describe George Washington’s leadership style. Northouse wrote, “Washington … as Schwartz (1987, p. 147) has suggested, ‘was ‘great’ because he was ‘good.’” If you wanted to cite Schwartz or use Schwartz’s quote in your paper, you must locate and read the original Schwartz material, to ensure that you quote or attribute Schwartz’s material accurately. Secondary citations are prone to errors. See the APA publication manual, article 6.17 (p. 178), for guidelines about citing secondary sources. Don’t use secondary sources to simply save time needed to research the original source. According to APA (2010), only use secondary sources “when the original work is out of print, unavailable through usual sources, or not available in English” (p. 178). And if you must use a secondary citation, use the following format for an in-text citation and cite only the secondary author(s), not the primary source, in the reference list: Northouse (2012) suggested that George Washington was a great leader because of his goodness (as cited in Schwartz, 1987).

NOTE 2: If you chose to write in a paper that “George Washington was a great leader,” you would not need to cite your source (e.g., Northouse, 2012, or Schwartz, 1987) because it is common knowledge that Washington, the first U.S. president, was a great leader. However, if you chose to quote Northouse, then you must cite the source of the quote.

NOTE 3: Do not “pad” your paper with citations or a long reference list in an attempt to have your paper seen as being more “scholarly” or to impress a professor. Papers that focus on a review of literature as their primary thesis or topic often contain lengthy reference lists. However, in most articles or papers, be judicious in your use of in-text and reference list citations. Articles or papers that borrow excessively from the work of other authors (e.g., an overabundance of in-text and reference list citations) are usually less credible than articles or papers with a reasonable number of citations that are based primarily on an author’s original work. Finally, when citing sources, make sure that all in-text citations appear on the reference list (with the exception of some elements of a secondary citation, as described in Note 1); and ensure that all sources listed in a reference list have a corresponding in-text citation.

References:

American Psychological Association, 2010. Publication manual of the American Psychological Association (6^th ed.). Washington, DC: Author.

Northouse, P. G., 2012. Introduction to leadership (2^nd ed.). Los Angeles: Sage.