MLA

Benét, William Rose, 1886-1950. Drake, Leah Bodine. Box 13, folder 497. 1948-1950, undated. https://collections.library.yale.edu/catalog/17204714.

APA, 6th edition

Benét, William Rose, 1886-1950. (["Box 13, folder 497"])(1948-1950, undated)[Drake, Leah Bodine]. https://collections.library.yale.edu/catalog/17204714.