MLA

Pound, Ezra, 1885-1972. Typescript. Box 71, folder 3178. n.d.. https://collections.library.yale.edu/catalog/16054046.

APA, 6th edition

Pound, Ezra, 1885-1972. (["Box 71, folder 3178"])(n.d.)[Typescript]. https://collections.library.yale.edu/catalog/16054046.