- Cite secondary sources sparingly—for instance, when the original work is out of print, unavailable, or available only in a language that you do not understand.
- If possible, as a matter of good scholarly practice, find the primary source, read it, and cite it directly rather than citing a secondary source. For example, rather than citing an instructor’s lecture or a textbook or encyclopedia that in turn cites original research, find, read, and cite the original research directly (unless an instructor has directed you to do otherwise).
Follow these directions when citing a secondary source:
- In the reference list, provide an entry for the secondary source that you used.
- In the in-text, identify the primary source and write “as cited in” the secondary source that you used.
If the year of publication of the primary source is known, also include it in the text citation.
For example, if you read a work by Lyon et al. (2014) in which Rabbitt (1982) was cited, and you were unable to read Rabbitt’s work yourself, cite Rabbitt’s work as the original source, followed by Lyon et al.’s work as the secondary source. Only Lyon et al.’s work appears in the reference list.
(Rabbitt, 1982, as cited in Lyon et al., 2014)
If the year of the primary source is unknown, omit it from the in-text citation.
Allport’s diary (as cited in Nicholson, 2003)
https://apastyle.apa.org/style-grammar-guidelines/citations/secondary-sources