MLA

Hughes, Langston, 1902-1967. Unidentified. Box 16, folder 194. 1875-1978. https://collections.library.yale.edu/catalog/16206983.

APA, 6th edition

Hughes, Langston, 1902-1967. (["Box 16, folder 194"])(1875-1978)[Unidentified]. https://collections.library.yale.edu/catalog/16206983.