MLA

Thayer, Scofield, 1889-1982. Erdberg, Robert von. Box 31, folder 816-838. 1910-23. https://collections.library.yale.edu/catalog/17142312.

APA, 6th edition

Thayer, Scofield, 1889-1982. (["Box 31, folder 816-838"])(1910-23)[Erdberg, Robert von]. https://collections.library.yale.edu/catalog/17142312.