MLA

Davis, Charles T. (Charles Twitchell), 1918-1981. Krumholz, Harlan. Box 6. [circa 1930s-1980]. https://collections.library.yale.edu/catalog/16769556.

APA, 6th edition

Davis, Charles T. (Charles Twitchell), 1918-1981. (["Box 6"])([circa 1930s-1980])[Krumholz, Harlan]. https://collections.library.yale.edu/catalog/16769556.