MLA

Pound, Ezra, 1885-1972. Notes. Box 78, folder 3433. n.d.. https://collections.library.yale.edu/catalog/17122695.

APA, 6th edition

Pound, Ezra, 1885-1972. (["Box 78, folder 3433"])(n.d.)[Notes]. https://collections.library.yale.edu/catalog/17122695.