MLA

Pound, Ezra, 1885-1972. Letters. Box 60, folder 2680. 1918. https://collections.library.yale.edu/catalog/2054689.

APA, 6th edition

Pound, Ezra, 1885-1972. (["Box 60, folder 2680"])(1918)[Letters]. https://collections.library.yale.edu/catalog/2054689.