MLA

Hughes, Langston, 1902-1967. Ward, Theodore. Box 167, folder 3066. 1938-67, n.d.. https://collections.library.yale.edu/catalog/31915965.

APA, 6th edition

Hughes, Langston, 1902-1967. (["Box 167, folder 3066"])(1938-67, n.d.)[Ward, Theodore]. https://collections.library.yale.edu/catalog/31915965.