MLA

Hughes, Langston, 1902-1967. National Negro Congress. Box 118, folder 2245. 1939-47. https://collections.library.yale.edu/catalog/32458339.

APA, 6th edition

Hughes, Langston, 1902-1967. (["Box 118, folder 2245"])(1939-47)[National Negro Congress]. https://collections.library.yale.edu/catalog/32458339.