MLA

Van Vechten, Carl, 1880-1964. Kaufman, Beatrice. Box 355 | Folder 4820. 1934 December 10. https://collections.library.yale.edu/catalog/2054510.

APA, 6th edition

Van Vechten, Carl, 1880-1964. (["Box 355 | Folder 4820"])(1934 December 10)[Kaufman, Beatrice]. https://collections.library.yale.edu/catalog/2054510.