MLA

Dimon, Charles Augustus Ropes, 1841-1902. Dakotah Territory. Box 8, folder 193. n.d.. https://collections.library.yale.edu/catalog/2008524.

APA, 6th edition

Dimon, Charles Augustus Ropes, 1841-1902. (["Box 8, folder 193"])(n.d.)[Dakotah Territory]. https://collections.library.yale.edu/catalog/2008524.