Sonnets: autograph ms.
MLA
Pound, Ezra, 1885-1972. Sonnets: autograph ms.. Box 80, folder 3549. [1910]. https://collections.library.yale.edu/catalog/17430566.
APA, 6th edition
Pound, Ezra, 1885-1972. (["Box 80, folder 3549"])([1910])[Sonnets: autograph ms.]. https://collections.library.yale.edu/catalog/17430566.