how do you cite a source that you found in another source

(adapted from the sixth edition of the APA Publication Manual , © 2010)
This page reflects guidance from the sixth edition of the Publication Manual.

Your in-text citation should include both authors: the author(s) of the original source and the author(s) of the secondary source. For example: (Habermehl, 1985, as cited in Kersten, 1987).
You should always try to read and cite the original work (the primary source). If it is not possible to do this, you have to cite the original as contained in the secondary source.

For example, if Allport’s work is cited in Nicholson and you did not read Allport’s work, list the Nicholson reference in the reference list. In the text, use something similar to the following citations:
For the reference list:

In your reference list, provide a reference for the source you read. This is known as the secondary source because it is one step removed from the original source of the idea or quotation. In your text, name the original work and provide the citation for the secondary source.
In his e-mails, Smith argued that asynchronous line dancing would be the next Internet meme (as cited in Jones, 2010).

In the list of references, record the publication you actually sourced.
Sometimes an author writes about research that someone else has done, but you are unable to track down the original research document. In this case, only include the source you did consult in your references because you did not read the original document. Use the words ‘cited in’ in the in-text citation to indicate you have not read the original research.

Stone, R. J. (2013). Managing human resources (4th ed.). Wiley.

In the reference list, provide an entry for the secondary source that you have read
In the text, identify the original work and write “as cited in” the secondary source that you have read.

References:

http://www.wur.nl/en/article/How-do-I-cite-a-source-I-found-in-another-source.htm
http://rasmussen.libanswers.com/faq/32434
http://asklibrary.com.edu/faq/63488
http://libguides.scu.edu.au/harvard/secondary-sources
http://www.canterbury.ac.nz/library/support/citations-and-referencing/apa-american-psychological-association-style/secondary-sources/
http://www.wikihow.com/Reference-Essays