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 (6th 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 (6th
ed.). Washington, DC: Author.
Northouse, P. G., 2012. Introduction
to leadership (2nd ed.). Los Angeles: Sage.
