MLA

Pound, Ezra, 1885-1972. [Notes for Introduction] Fenollosa: by E. P.: typescript. Box 103, folder 4274. 1903 1975. https://collections.library.yale.edu/catalog/17122752.

APA, 6th edition

Pound, Ezra, 1885-1972. (["Box 103, folder 4274"])(1903 1975)[[Notes for Introduction] Fenollosa: by E. P.: typescript]. https://collections.library.yale.edu/catalog/17122752.