MLA

Van Vechten, Carl, 1880-1964. Goossens, Eugene, Sir. Box 350, folder 4675. 1945 March 31. https://collections.library.yale.edu/catalog/2035525.

APA, 6th edition

Van Vechten, Carl, 1880-1964. (["Box 350, folder 4675"])(1945 March 31)[Goossens, Eugene, Sir]. https://collections.library.yale.edu/catalog/2035525.