MLA

Hughes, Langston, 1902-1967. Lynd, Staughton. Box 105, folder 1994. 1964 Apr. https://collections.library.yale.edu/catalog/33480973.

APA, 6th edition

Hughes, Langston, 1902-1967. (["Box 105, folder 1994"])(1964 Apr)[Lynd, Staughton]. https://collections.library.yale.edu/catalog/33480973.