MLA

Van Vechten, Carl, 1880-1964. Van Vechten, Carl. Box 379, folder 5600. 1936 March 15. https://collections.library.yale.edu/catalog/10608168.

APA, 6th edition

Van Vechten, Carl, 1880-1964. (["Box 379, folder 5600"])(1936 March 15)[Van Vechten, Carl]. https://collections.library.yale.edu/catalog/10608168.