MLA

Pound, Ezra, 1885-1972. Typescripts. Box 72, folder 3228. n.d.. https://collections.library.yale.edu/catalog/16169367.

APA, 6th edition

Pound, Ezra, 1885-1972. (["Box 72, folder 3228"])(n.d.)[Typescripts]. https://collections.library.yale.edu/catalog/16169367.