MLA

Pound, Ezra, 1885-1972. "Sinn Fein": typescript. Box 133, folder 5693. [1941] Jul 12. https://collections.library.yale.edu/catalog/17122858.

APA, 6th edition

Pound, Ezra, 1885-1972. (["Box 133, folder 5693"])([1941] Jul 12)["Sinn Fein": typescript]. https://collections.library.yale.edu/catalog/17122858.