MLA

Van Vechten, Carl, 1880-1964. Gallup, Donald Clifford, with Herman W. Liebert, Chauncey Brewster Tinker, and Carl Van Vechten. Box 111, folder 2078. 1950 January 7. https://collections.library.yale.edu/catalog/2028906.

APA, 6th edition

Van Vechten, Carl, 1880-1964. (["Box 111, folder 2078"])(1950 January 7)[Gallup, Donald Clifford, with Herman W. Liebert, Chauncey Brewster Tinker, and Carl Van Vechten]. https://collections.library.yale.edu/catalog/2028906.