How do I cite something that's cited in another source?

Citing a Source Within A Source MLA, APA, and Chicago styles all encourage you to find the original source for citation. If you cannot and have to cite a source within the source, you have to list both sources in the in-text citation. For example, you could be citing a quote from an article listed in a book. This is known as secondary citation. For an in-text citation, you would cite the primary source you are taking information from and then cite the secondary source at the end of the citation. Your reference list will only list the secondary source for MLA and APA Format. Chicago Style requires you to list both sources in the Reference List. MLA Format Secondary Sources: University of Newcastle APA Format Secondary Sources: George Washington University Chicago Format Secondary Sources: Simon Fraser University