MLA

Gilman, Daniel C. (Daniel Coit), 1831-1908. Silliman, Benjamin. Box 2, folder 128. 1873. https://collections.library.yale.edu/catalog/32522646.

APA, 6th edition

Gilman, Daniel C. (Daniel Coit), 1831-1908. (["Box 2, folder 128"])(1873)[Silliman, Benjamin]. https://collections.library.yale.edu/catalog/32522646.