Specific examples pertaining any secondary sources examples
When you cite an author who refers to or quotes another author, this must be clearly indicated in the text (even though this practice should be kept to a minimum as the preferred option is for you to have read the original source itself).
Chambers (1983, p. 25) gives Whiteley’s (1979) definition of emotion as “a response to situations of one specific type ...”
In this example, the reference actually used was Chambers (1983), not Whiteley (1979).
A reference list entry must be made for Chambers, but can be made for both items if it is useful to your reader.
Reference: Chambers, P.K. (1983). Your emotions revealed. New York: Lacrima and Ductule.
Reference: Whiteley, B.C. (1979). ‘Emotional response’, Brain Talk, vol. 2, no. 12, pp. 234-5. (optional at your discretion)