Sometimes the author of a source may use a quote or paraphrase an idea from another source. This is called an indirect source.
For example, the article you are reading was written by Kirkey, but they included a quotation by Smith that you would like to use in your essay.
The basic rule is that you would cite the source you are using in both your References list and in-text citation. Using the example, you would cite the work by Kirkey and not Smith. To help identify that the quote or paraphrase is from another author's work, you will add the words "as cited in" to your in-text citation.
In-Text Citation Example:
According to a study by Smith (as cited in Kirkey, 2013) 42% of doctors would refuse to perform legal euthanasia.
Smith (as cited in Kirkey, 2013) states that “even if euthanasia was legal, 42% of doctors would be against this method of assisted dying” (p. 34).
References List Example:
Kirkey, S. (2013, Feb 9). Euthanasia. The Montreal Gazette, p. A10.