MLA

Hughes, Langston, 1902-1967. Williams, Bert; Williams, Lottie. Box 12 (Oversize), folder 137. 1903, 1931, undated. https://collections.library.yale.edu/catalog/16206936.

APA, 6th edition

Hughes, Langston, 1902-1967. (["Box 12 (Oversize), folder 137"])(1903, 1931, undated)[Williams, Bert; Williams, Lottie]. https://collections.library.yale.edu/catalog/16206936.