Curtis, K. H. (1957). Correspondence, July 30, 1957 through August 21, 1957. Saint Louis University Libraries Digitization Center.
Chicago-viite (17. p.)Curtis, Kennth; Heuduck. Correspondence, July 30, 1957 Through August 21, 1957. Saint Louis University Libraries Digitization Center, 1957.
MLA-viite (8. p.)Curtis, Kennth; Heuduck. Correspondence, July 30, 1957 Through August 21, 1957. Saint Louis University Libraries Digitization Center, 1957.
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