MLA

Wescott, Glenway, 1901-1987. Butts, Mary. Box 41, folder 553. 1923-27, n.d.. https://collections.library.yale.edu/catalog/31908712.

APA, 6th edition

Wescott, Glenway, 1901-1987. (["Box 41, folder 553"])(1923-27, n.d.)[Butts, Mary]. https://collections.library.yale.edu/catalog/31908712.