MLA

Butts, Mary, 1890-1937. "A Free Man to a Free Woman," typescript carbon. Box 5, folder 92. n.d.. https://collections.library.yale.edu/catalog/16586538.

APA, 6th edition

Butts, Mary, 1890-1937. (["Box 5, folder 92"])(n.d.)["A Free Man to a Free Woman," typescript carbon]. https://collections.library.yale.edu/catalog/16586538.