MLA
Fredericks, Charles D., and Co. Unknown Union Naval[?] Officer. Charles D. Fredericks & Co., 1861. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 22, Folder 50. https://digital.library.emory.edu/purl/559q2bvrdw-cor.
APA, 6th edition
Fredericks, C. D., & C. (1861). Unknown Union naval[?] officer (Box 22, Folder 50) [Cartes-de-visite (card photographs)]. Charles D. Fredericks & Co.; Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/559q2bvrdw-cor.
Chicago
Fredericks, Charles D., and Co. “Unknown Union Naval[?] Officer.” Cartes-de-visite (card photographs). Civil War Collection. New York City, NY: Charles D. Fredericks & Co., 1861. Box 22, Folder 50. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/559q2bvrdw-cor.