MLA
Eno, Henry C. Lithograph of a Union Military Post in Cowan, Tennessee, from a Drawing by Sergeant N. B. Abbott. 1864. Stuart A. Rose Manuscript, Archives, and Rare Book Library, OP9, Folder 23. https://digital.library.emory.edu/purl/955m905rqd-cor.
APA, 6th edition
Eno, H. C. (1864). Lithograph of a Union military post in Cowan, Tennessee, from a drawing by Sergeant N. B. Abbott (OP9, Folder 23) [Lithographs]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/955m905rqd-cor.
Chicago
Eno, Henry C. “Lithograph of a Union Military Post in Cowan, Tennessee, from a Drawing by Sergeant N. B. Abbott.” Lithographs. Civil War Collection. New York City, NY, 1864. OP9, Folder 23. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/955m905rqd-cor.