MLA

Van Vechten, Carl, 1880-1964. Bontemps, Arna. Box 207, folder 3513. 1939 August 15. https://collections.library.yale.edu/catalog/2021039.

APA, 6th edition

Van Vechten, Carl, 1880-1964. (["Box 207, folder 3513"])(1939 August 15)[Bontemps, Arna]. https://collections.library.yale.edu/catalog/2021039.