MLA
Turner, A. A. (Austin Augustus), approximately 1831-1866. Union general Robert Anderson. Anderson commanded Fort Sumter at the start of the Civil War. 1861?/1880?. Civil War Collection. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/003cz8wb66-cor.
APA, 6th edition
Turner, A. A. (Austin Augustus), approximately 1831-1866. (1861?/1880?)[Union general Robert Anderson. Anderson commanded Fort Sumter at the start of the Civil War]. Civil War Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/003cz8wb66-cor.
Chicago
Turner, A. A. (Austin Augustus), approximately 1831-1866, Union general Robert Anderson. Anderson commanded Fort Sumter at the start of the Civil War, 1861?/1880?, Civil War Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/003cz8wb66-cor.