MLA

Simpson, Randolph Linsly, 1927-1992. Keystone View Company, Meadville, PA; New York, NY; Chicago, IL; London, ENG. "P147 - 18206. The Blacksmith's Shop." Stereograph, grey card. Box 13, folder 624. circa 1896. https://collections.library.yale.edu/catalog/32582580.

APA, 6th edition

Simpson, Randolph Linsly, 1927-1992. (["Box 13, folder 624"])(circa 1896)[Keystone View Company, Meadville, PA; New York, NY; Chicago, IL; London, ENG. "P147 - 18206. The Blacksmith's Shop." Stereograph, grey card]. https://collections.library.yale.edu/catalog/32582580.