MLA
Smyth, Thomas, 1808-1873. The sin and the curse, or, The Union, the true source of disunion, and our duty in the present crisis : a discourse preached on the occasion of the day of humiliation and prayer appointed by the governor of South Carolina, on November 21st, 1860, in the Second Presbyterian Church, Charleston, S.C.. 1860. Civil War Imprints. Emory University. General Libraries. https://digital.library.emory.edu/purl/491fj6q8vw-cor.
APA, 6th edition
Smyth, Thomas, 1808-1873. (1860)[The sin and the curse, or, The Union, the true source of disunion, and our duty in the present crisis : a discourse preached on the occasion of the day of humiliation and prayer appointed by the governor of South Carolina, on November 21st, 1860, in the Second Presbyterian Church, Charleston, S.C.]. Civil War Imprints, Emory University. General Libraries. https://digital.library.emory.edu/purl/491fj6q8vw-cor.
Chicago
Smyth, Thomas, 1808-1873, The sin and the curse, or, The Union, the true source of disunion, and our duty in the present crisis : a discourse preached on the occasion of the day of humiliation and prayer appointed by the governor of South Carolina, on November 21st, 1860, in the Second Presbyterian Church, Charleston, S.C., 1860, Civil War Imprints, Emory University. General Libraries. https://digital.library.emory.edu/purl/491fj6q8vw-cor.