MLA
Nichols, William H. The Siege and Capture of Harper's Ferry by the Confederates, September, 1862. Published by the Society, 1889. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/5053ffbm87-cor.
APA, 6th edition
Nichols, W. H. (1889). The siege and capture of Harper's Ferry by the Confederates, September, 1862. Published by the Society; Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/5053ffbm87-cor.
Chicago
Nichols, William H. “The Siege and Capture of Harper's Ferry by the Confederates, September, 1862.” Regimental Histories. Providence: Published by the Society, 1889. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/5053ffbm87-cor.