Sometimes you want to refer to a book, article, etc. that you have not read yourself, but which is mentioned in another source, which you have read.
For example, you have read the book A Devil’s Chaplain, by Richard Dawkins. On page 140 he refers to a theory of Amotz Zahavi about the evolution of peacocks’ tails:
Zahavi suggests that peacocks, for instance, evolve their absurdly burdensome fans with their ridiculously conspicuous (to predators) colours, precisely because they are burdensome and dangerous, and therefore impressive to females.
You would like to mention this theory, which Zahavi proposed in a journal article in 1975.
- The original article by Zahavi (published in 1975) is the primary source.
- The book by Dawkins (published in 2003) that mentions Zahavi’s theory is the secondary source.
Your in-text citation
Use this formula: primary source cited in secondary source:
It has even been argued that - by encumbering and imperilling him - the peacock’s ostentatious plumage makes him more attractive to potential mates (Zahavi, 1975, cited in Dawkins, 2003, p. 140).
Your reference list
Your reference list should include only those sources that you have actually read.
You have read the book by Dawkins, but not the article by Zahavi. Include Dawkins in your reference list, but not Zahavi.
Dawkins, R. (2003) A devil’s chaplain: selected essays. London: Weidenfeld & Nicolson.