MLA

Hughes, Langston, 1902-1967. Musical outlines. Box 367, folder 5916. 1939 Feb. https://collections.library.yale.edu/catalog/17034074.

APA, 6th edition

Hughes, Langston, 1902-1967. (["Box 367, folder 5916"])(1939 Feb)[Musical outlines]. https://collections.library.yale.edu/catalog/17034074.