MLA

Hughes, Langston, 1902-1967. Abramson, Doris. Box 2, folder 19. 1963. https://collections.library.yale.edu/catalog/32604201.

APA, 6th edition

Hughes, Langston, 1902-1967. (["Box 2, folder 19"])(1963)[Abramson, Doris]. https://collections.library.yale.edu/catalog/32604201.