MLA

Van Vechten, Carl, 1880-1964. Attaway, William. Box 223. 1941 October 29. https://collections.library.yale.edu/catalog/2022208.

APA, 6th edition

Van Vechten, Carl, 1880-1964. (["Box 223"])(1941 October 29)[Attaway, William]. https://collections.library.yale.edu/catalog/2022208.