MLA

Hughes, Langston, 1902-1967. "Two Festivals: Stratford And Newport" [1958 Aug 16], drafts, carbon, corrected. Box 414, folder 8958. 1958 Aug 4. https://collections.library.yale.edu/catalog/17394780.

APA, 6th edition

Hughes, Langston, 1902-1967. (["Box 414, folder 8958"])(1958 Aug 4)["Two Festivals: Stratford And Newport" [1958 Aug 16], drafts, carbon, corrected]. https://collections.library.yale.edu/catalog/17394780.