MLA
Unidentified Confederate Soldier[?]. Usher's Gallery, 1861. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 17, Folder 26. https://digital.library.emory.edu/purl/904dncjv50-cor.
APA, 6th edition
Unidentified Confederate soldier[?] (Box 17, Folder 26). (1861). [Cartes-de-visite (card photographs)]. Usher's Gallery; Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/904dncjv50-cor.
Chicago
“Unidentified Confederate Soldier[?].” Cartes-de-visite (card photographs). Civil War Collection. Augusta, GA: Usher's Gallery, 1861. Box 17, Folder 26. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/904dncjv50-cor.