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Chicago Referencing

Sources referring to other sources

  • In your research you will often encounter resources where an author refers to another researcher's work. A source within another source is known as a secondary source.
  • Generally it is discouraged to cite a source from within another source as you are expected to have consulted the work directly. However sometimes this is not possible. In these cases the footnote should list both the original source first, joined by words such as "quoted in" or "discussed in" and then list the secondary source.


23 Louis Zukofsky, “Sincerity and Objectification,” Poetry 37 (February 1931): 269, quoted in Bonnie Costello, Marianne Moore: Imaginary Possessions (Cambridge, MA: Harvard University Press, 1981), 78.

Bibliography entry

The bibliography must include both the original source and the secondary source. Using the example above the two entries will be:

Costello, Bonnie. Marianne Moore: Imaginary Possessions. Cambridge, MA: Harvard University Press, 1981.

Zukofsky, Louis. "Sincerity and Objectification: With Special Reference to the Work of Charles Reznikoff." Poetry 37, no. 5 (February 1931): 272-85.