MLA

Pound, Ezra, 1885-1972. Isolated Superiority: typescripts. Box 144, folder 6325. n.d.. https://collections.library.yale.edu/catalog/17122872.

APA, 6th edition

Pound, Ezra, 1885-1972. (["Box 144, folder 6325"])(n.d.)[Isolated Superiority: typescripts]. https://collections.library.yale.edu/catalog/17122872.