MLA

McKay, Claude, 1890-1948. "Outcast," typescript carbon. Box 12, folder 388. n.d.. https://collections.library.yale.edu/catalog/32269420.

APA, 6th edition

McKay, Claude, 1890-1948. (["Box 12, folder 388"])(n.d.)["Outcast," typescript carbon]. https://collections.library.yale.edu/catalog/32269420.