MLA

Van Vechten, Carl, 1880-1964. Davison, Robert. Box 343, folder 4456. 1948 May 2. https://collections.library.yale.edu/catalog/2032467.

APA, 6th edition

Van Vechten, Carl, 1880-1964. (["Box 343, folder 4456"])(1948 May 2)[Davison, Robert]. https://collections.library.yale.edu/catalog/2032467.