When possible, it is best to try to find the original source and cite that. If you are unable to find the original source of the quote, you can use the citation methods below.
In-text
MLA Style
Use a signal phrase to introduce the quote and give credit to the person who said it. Then use "qtd. in" in your parenthetical citation to give credit to the work where you found the quote.
Example: Larsen writes, “Today’s librarian is part teacher, part entrepreneur” (qtd. in Brown 424).
APA Style
Use a signal phrase to introduce the quote and give credit to the person who said it. Then use "qtd. in" in your parenthetical citation to give credit to the work where you found the quote.
Example: In Seidenberg and McCelland's study (as cited in Coltheart, Curtis, Atkins, & Haller, 1993)...
Works Cited or Reference Page
MLA Style
Cite the work you found the quote in. For the example above, you would cite Brown's work, not Larsen's.
APA Style
Cite the work you found the quote in. For the example above, cite Coltheart, M., Curtis, B., Atkins, P., & Haller, M., not Seidenberg and McCelland.