MLA

Van Vechten, Carl, 1880-1964. Tudor, Antony. Box 378, folder 5524. 1940 March 3. https://collections.library.yale.edu/catalog/10563586.

APA, 6th edition

Van Vechten, Carl, 1880-1964. (["Box 378, folder 5524"])(1940 March 3)[Tudor, Antony]. https://collections.library.yale.edu/catalog/10563586.