MLA

Van Vechten, Carl, 1880-1964. McClintic, Guthrie. Box 367 | Folder 5144. 1938 February 18. https://collections.library.yale.edu/catalog/2065471.

APA, 6th edition

Van Vechten, Carl, 1880-1964. (["Box 367 | Folder 5144"])(1938 February 18)[McClintic, Guthrie]. https://collections.library.yale.edu/catalog/2065471.