MLA

Clark, Eleanor, 1913-1996. Capote, Truman. Box 27, folder 331. 1959-1965. https://collections.library.yale.edu/catalog/17123995.

APA, 6th edition

Clark, Eleanor, 1913-1996. (["Box 27, folder 331"])(1959-1965)[Capote, Truman]. https://collections.library.yale.edu/catalog/17123995.