How do I cite a source that uses another source within?

I’m not sure about MLA or Chicago style, but at least in APA you would say “Author Y as cited in Author X (year)”.

Be careful when quoting large sections for any sort of academic paper, some professors prefer “brevity”.

@everephebe not talking long quotes here, just even a short blip.

Smith, John. In Michael Jones, Frankie Goes to the Grocery Store. City: Publisher, 1990, pp. 1–4.

I would have to see the context, but as long as author X is properly citing author Y in his work, then you should be able to simply cite author X in your in-text and bibliography cites. If there’s a quote from author Y in your quote from author X, then simply reduce author Y’s quote to single quotes, and frame the entirety of the section from author X in double quotes.

For Chicago, you cite the source you read, not the original source, since technically you didn’t read the original source but something with the original sources work. For example, one of my books Spartacus and the Slave Wars has the documents relating to it, written by (among others) Cissero. However, I’m not actually reading all that Cissero wrote, I’m reading Brad Shaw’s translation of a portion of what Cissero wrote. If that makes any sense.

I usually say ‘per so and so as quoted in blank’