MLA

Van Vechten, Carl, 1880-1964. Barnett, Etta Moten. Box 83, folder 1386. 1934 March 16. https://collections.library.yale.edu/catalog/2026979.

APA, 6th edition

Van Vechten, Carl, 1880-1964. (["Box 83, folder 1386"])(1934 March 16)[Barnett, Etta Moten]. https://collections.library.yale.edu/catalog/2026979.