MLA

Van Vechten, Carl, 1880-1964. Gross, Chaim. Box 351, folder 4701. 1963 May 14. https://collections.library.yale.edu/catalog/2036153.

APA, 6th edition

Van Vechten, Carl, 1880-1964. (["Box 351, folder 4701"])(1963 May 14)[Gross, Chaim]. https://collections.library.yale.edu/catalog/2036153.