MLA
Chappel, Alonzo, 1828-1887. Union general Benjamin Butler. 1861?/1880?. Civil War Collection. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/4407wm38ss-cor.
APA, 6th edition
Chappel, Alonzo, 1828-1887. (1861?/1880?)[Union general Benjamin Butler]. Civil War Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/4407wm38ss-cor.
Chicago
Chappel, Alonzo, 1828-1887, Union general Benjamin Butler, 1861?/1880?, Civil War Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/4407wm38ss-cor.