Secondary referencing or indirect citation is when you cite a source that you have not read, but that is cited in the document you are reading. Of course, it is strongly recommended to check the citation in the original document if possible. But if this is not possible, both documents should be included in the citation, with the cited document being "quoted in" (if the second author quotes the first author directly) or "cited in" (if the second author is paraphrasing/summarizing the first).
Example 1 (Chicago note style): Simone de Beauvoir's book, The Second Sex, is referenced in a journal article by Judith Butler
1. Simone de Beauvoir, The Second Sex (New York: Vintage, 1974), 38, quoted in Judith Butler, "Performative Acts and Gender Constitution: An Essay in Phenomenology and Feminist Theory," Theatre Journal 40, no. 4 (1988): 519.
Example 2 (APA, author-date style): Simone de Beauvoir (as quoted in Butler, 1988, p. 519)
Most authors consider that you should only include documents that you have actually read in the reference list, and therefore not documents that you cite indirectly.