MLA

Pratt, Richard Henry, 1840-1924. [11] Prisoners arriving at Caddo. Box 31. 1875 May 5. https://collections.library.yale.edu/catalog/2001766.

APA, 6th edition

Pratt, Richard Henry, 1840-1924. (["Box 31"])(1875 May 5)[[11] Prisoners arriving at Caddo]. https://collections.library.yale.edu/catalog/2001766.