MLA

Van Vechten, Carl, 1880-1964. Walker, Stuart. Box 381, folder 5667. 1933 November 29. https://collections.library.yale.edu/catalog/10623825.

APA, 6th edition

Van Vechten, Carl, 1880-1964. (["Box 381, folder 5667"])(1933 November 29)[Walker, Stuart]. https://collections.library.yale.edu/catalog/10623825.