MLA

Van Vechten, Carl, 1880-1964. Chase, Ilka. Box 664, folder 14639. 1933 October 12. https://collections.library.yale.edu/catalog/33270851.

APA, 6th edition

Van Vechten, Carl, 1880-1964. (["Box 664, folder 14639"])(1933 October 12)[Chase, Ilka]. https://collections.library.yale.edu/catalog/33270851.