MLA

Pound, Ezra, 1885-1972. Mallon, Bertram: typescript. Box 111, folder 4713. n.d.. https://collections.library.yale.edu/catalog/17122796.

APA, 6th edition

Pound, Ezra, 1885-1972. (["Box 111, folder 4713"])(n.d.)[Mallon, Bertram: typescript]. https://collections.library.yale.edu/catalog/17122796.