MLA

Van Vechten, Carl, 1880-1964. Isherwood, Christopher, at Taos, New Mexico. Box 354 | Folder 4793. 1950 August 17. https://collections.library.yale.edu/catalog/2054294.

APA, 6th edition

Van Vechten, Carl, 1880-1964. (["Box 354 | Folder 4793"])(1950 August 17)[Isherwood, Christopher, at Taos, New Mexico]. https://collections.library.yale.edu/catalog/2054294.