MLA

Van Vechten, Carl, 1880-1964. Barthelmess, Richard, in Malibu, California. Box 335, folder 4202. 1933 July 19. https://collections.library.yale.edu/catalog/2030517.

APA, 6th edition

Van Vechten, Carl, 1880-1964. (["Box 335, folder 4202"])(1933 July 19)[Barthelmess, Richard, in Malibu, California]. https://collections.library.yale.edu/catalog/2030517.