MLA

Thayer, Scofield, 1889-1982. Perkins, Harley. Box 37, folder 1042. 1924-25. https://collections.library.yale.edu/catalog/11371910.

APA, 6th edition

Thayer, Scofield, 1889-1982. (["Box 37, folder 1042"])(1924-25)[Perkins, Harley]. https://collections.library.yale.edu/catalog/11371910.