MLA

Pound, Ezra, 1885-1972. Polverilli, Gaetano. Box 41, folder 1745-1746. 1932-42. https://collections.library.yale.edu/catalog/17122614.

APA, 6th edition

Pound, Ezra, 1885-1972. (["Box 41, folder 1745-1746"])(1932-42)[Polverilli, Gaetano]. https://collections.library.yale.edu/catalog/17122614.