MLA

Hughes, Langston, 1902-1967. Nussbaum, Anna. Box 121, folder 2290. 1927-29. https://collections.library.yale.edu/catalog/17020444.

APA, 6th edition

Hughes, Langston, 1902-1967. (["Box 121, folder 2290"])(1927-29)[Nussbaum, Anna]. https://collections.library.yale.edu/catalog/17020444.