Curtis, K. H. (1957). Correspondence, July 30, 1957 through August 21, 1957. Saint Louis University Libraries Digitization Center.
Chicago-referens (17:e uppl.)Curtis, Kennth; Heuduck. Correspondence, July 30, 1957 Through August 21, 1957. Saint Louis University Libraries Digitization Center, 1957.
MLA-referens (8:e uppl.)Curtis, Kennth; Heuduck. Correspondence, July 30, 1957 Through August 21, 1957. Saint Louis University Libraries Digitization Center, 1957.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.