MLA

Clark, Eleanor, 1913-1996. Naginski, Charles. Box 31, folder 431-433. 1938-1939. https://collections.library.yale.edu/catalog/17123997.

APA, 6th edition

Clark, Eleanor, 1913-1996. (["Box 31, folder 431-433"])(1938-1939)[Naginski, Charles]. https://collections.library.yale.edu/catalog/17123997.