Cite

Knight, Eric, with horses

MLA

Knight, Eric, 1897-1943. Knight, Eric, with horses. Box 15, folder 338. n.d.. https://collections.library.yale.edu/catalog/2014301.

APA, 6th edition

Knight, Eric, 1897-1943. (["Box 15, folder 338"])(n.d.)[Knight, Eric, with horses]. https://collections.library.yale.edu/catalog/2014301.