MLA

Brush, George Jarvis, 1831-1912. Genth Frederick Augustus (42). Box 2, folder 53. 1857. https://collections.library.yale.edu/catalog/32513153.

APA, 6th edition

Brush, George Jarvis, 1831-1912. (["Box 2, folder 53"])(1857)[Genth Frederick Augustus (42)]. https://collections.library.yale.edu/catalog/32513153.