MLA

Hughes, Langston, 1902-1967. American Student Union. Box 7, folder 145. 1936-38. https://collections.library.yale.edu/catalog/32585006.

APA, 6th edition

Hughes, Langston, 1902-1967. (["Box 7, folder 145"])(1936-38)[American Student Union]. https://collections.library.yale.edu/catalog/32585006.