MLA

Pound, Ezra, 1885-1972. Cerio, F. Ferruccio. Box 8, folder 367. 1934. https://collections.library.yale.edu/catalog/17122533.

APA, 6th edition

Pound, Ezra, 1885-1972. (["Box 8, folder 367"])(1934)[Cerio, F. Ferruccio]. https://collections.library.yale.edu/catalog/17122533.