MLA

Thayer, Scofield, 1889-1982. Thayer, Scofield. Box 57, folder 1531-1533. 1903-12, n.d.. https://collections.library.yale.edu/catalog/10034098.

APA, 6th edition

Thayer, Scofield, 1889-1982. (["Box 57, folder 1531-1533"])(1903-12, n.d.)[Thayer, Scofield]. https://collections.library.yale.edu/catalog/10034098.