MLA

Simpson, Randolph Linsly, 1927-1992. John C. Taylor, Hartford, CT Stamped recto, "The War for the Union, Photographic History." Mounted recto from verso, "Redoubt Zabriskie, group of negro army teamsters, 2594." Stereograph, orange card. Box 12, folder 555. 1890. https://collections.library.yale.edu/catalog/2005532.

APA, 6th edition

Simpson, Randolph Linsly, 1927-1992. (["Box 12, folder 555"])(1890)[John C. Taylor, Hartford, CT Stamped recto, "The War for the Union, Photographic History." Mounted recto from verso, "Redoubt Zabriskie, group of negro army teamsters, 2594." Stereograph, orange card]. https://collections.library.yale.edu/catalog/2005532.