Picture the situation: you're reading a perfectly good article when the author quotes someone else – someone whose original work you haven't tracked down, can't access, or simply don't have time to locate. You want to use the idea, but what do you do?
Luckily, APA has a clear answer for exactly this predicament, and it's called the secondary source citation.
A secondary source is any source that discusses, quotes, or paraphrases material from an original (primary) source that you have not personally read. The author you are reading is your secondary source. The author they are citing – the one you haven't read – is your primary source.
When is this appropriate?
APA 7th Edition is candid about the hierarchy here. The Publication Manual says secondary sources should be used "sparingly" and recommends that you track down and read the original source whenever possible. Secondary sourcing is a workaround, not a first choice. It is most appropriate when:
- The original work is genuinely out of print or unavailable.
- The original is in a language you cannot read.
- The idea is only tangentially related to your argument, and pursuing the primary source would be disproportionate to its role in your paper.
If you're building a central argument around a source, go find that source. Secondary sourcing for a key claim is a shaky foundation. You're trusting someone else's reading of a text you haven't verified.
The in-text citation format
In your paper's body, you name the original author (the one you didn't read) and note that their work is cited in the secondary source (the one you did read). The parenthetical citation includes both the primary and secondary source, but only the secondary source appears in your reference list.
Here's an example:
Early research suggested the migration patterns of the Sasquatch covered far greater distances than expected (Doughty, 1885, as cited in Livingston et al., 2013).
"As cited in" signals to the reader that you are working from a secondhand account. The primary source's year is optional in the parenthetical – include it if you know it, and if it adds context.
The reference list: One entry, not two
Here is where many students go wrong: they list both sources in the reference list, or they list only the primary source. In APA 7, neither is correct.
Your reference list contains only the source you actually read – the secondary source. The primary source goes unrecorded in references, though it appears in your in-text citation. Here's what that looks like:
Livingston, S., Paulson, K. A., Quint, E. J., Roth, M. J., & Willingham, D. T. (2013). Tracking the migration of Sasquatch with new mapping techniques. Cryptozoology Quarterly, 14(1), 4-26. https://doi.org/10.xxxx/xyz
Notice there is no Doughty reference at all. Your reference list is a record of what you consulted. Since you consulted Livingston et al. – not Doughty – only Livingston et al. is included on your reference list.
Format the secondary source entry exactly as you would any other source of its type. There is no special annotation required. The "as cited in" language in your in-text citation already does the explanatory work.
A few complications worth knowing
What if you know the original year but not the full citation? Include the original year in the in-text citation if it is known and meaningful. You are not required to track down the full primary source citation just to complete this parenthetical. If you know the year, use it; if not, omit it.
What about page numbers for a direct quote? If the secondary source provides a page number for the quoted passage, you may include it. If not, you are not obligated to supply one you don't have. Transparency is the goal. Never fabricate a page number from a source you haven't read.
Can you cite a secondary source multiple times? Yes, and you handle it the same way each time. This can get mildly repetitive, which is part of why APA nudges you toward locating the original.
The larger principle
APA's approach to secondary sourcing reflects a broader ethic running through the entire citation system: your references should be a faithful record of your actual scholarly encounter with the literature. Listing a source you haven't read implies you have read it. The "as cited in" construction exists precisely to let you be honest, to acknowledge the chain of transmission without misrepresenting your own engagement with the evidence.
Used sparingly and transparently, secondary citations are a perfectly legitimate part of academic writing. Used as a shortcut to pad your reference list with impressive-looking primary sources, they undermine the whole enterprise. APA trusts you to know the difference.