MLA

Pound, Ezra, 1885-1972. Hesse, Eva. Box 22, folder 968-973. 1952-63. https://collections.library.yale.edu/catalog/17122574.

APA, 6th edition

Pound, Ezra, 1885-1972. (["Box 22, folder 968-973"])(1952-63)[Hesse, Eva]. https://collections.library.yale.edu/catalog/17122574.