MLA

Gilman, Daniel C. (Daniel Coit), 1831-1908. Young, Mason. Box 2, folder 157. 1872. https://collections.library.yale.edu/catalog/32522663.

APA, 6th edition

Gilman, Daniel C. (Daniel Coit), 1831-1908. (["Box 2, folder 157"])(1872)[Young, Mason]. https://collections.library.yale.edu/catalog/32522663.