MLA
Krebbs, S. H., and Co. Cutting Rice, Helena, Ark. : [African Americans with Horses Cutting Rice in a Field] [Hand Colored]. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 68. https://digital.library.emory.edu/purl/3009w0vt7d-cor.
APA, 6th edition
Krebbs, S. H., & C. Cutting rice, Helena, Ark. : [African Americans with horses cutting rice in a field] [hand colored] (Box 68) [Postcards]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/3009w0vt7d-cor.
Chicago
Krebbs, S. H., and Co. “Cutting Rice, Helena, Ark. : [African Americans with Horses Cutting Rice in a Field] [Hand Colored].” Postcards. Robert Langmuir African American Photograph Collection, n.d. Box 68. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/3009w0vt7d-cor.