MLA

Geary, John White, 1819-1873. Promotions and recommendations. Box 2, folder 42. n.d.. https://collections.library.yale.edu/catalog/16700668.

APA, 6th edition

Geary, John White, 1819-1873. (["Box 2, folder 42"])(n.d.)[Promotions and recommendations]. https://collections.library.yale.edu/catalog/16700668.