MLA

Butts, Mary, 1890-1937. "Earth's Sacraments (2)," typescript carbon. Box 5, folder 91. n.d.. https://collections.library.yale.edu/catalog/16586537.

APA, 6th edition

Butts, Mary, 1890-1937. (["Box 5, folder 91"])(n.d.)["Earth's Sacraments (2)," typescript carbon]. https://collections.library.yale.edu/catalog/16586537.