MLA

Simpson, Randolph Linsly, 1927-1992. Unknown photographer Philadelphia Group of men, women, children stand under tree, tropical growth, along river bank. Stereograph, yellow card. Box 13, folder 692. circa 1868. https://collections.library.yale.edu/catalog/32582724.

APA, 6th edition

Simpson, Randolph Linsly, 1927-1992. (["Box 13, folder 692"])(circa 1868)[Unknown photographer Philadelphia Group of men, women, children stand under tree, tropical growth, along river bank. Stereograph, yellow card]. https://collections.library.yale.edu/catalog/32582724.