MLA

Van Vechten, Carl, 1880-1964. Franklin, Sidney. Box 348 | Folder 4620. 1951 September 21. https://collections.library.yale.edu/catalog/2034757.

APA, 6th edition

Van Vechten, Carl, 1880-1964. (["Box 348 | Folder 4620"])(1951 September 21)[Franklin, Sidney]. https://collections.library.yale.edu/catalog/2034757.