MLA

Butts, Mary, 1890-1937. "Nocturne II," typescript carbon. Box 5, folder 86. n.d.. https://collections.library.yale.edu/catalog/16586533.

APA, 6th edition

Butts, Mary, 1890-1937. (["Box 5, folder 86"])(n.d.)["Nocturne II," typescript carbon]. https://collections.library.yale.edu/catalog/16586533.