MLA

Van Vechten, Carl, 1880-1964. Atkinson, Edward. Box 83, folder 1362. 1943 February 3. https://collections.library.yale.edu/catalog/2020446.

APA, 6th edition

Van Vechten, Carl, 1880-1964. (["Box 83, folder 1362"])(1943 February 3)[Atkinson, Edward]. https://collections.library.yale.edu/catalog/2020446.