MLA
Elliott, Stephen, 1806-1866. Our cause in harmony with the purposes of God in Christ Jesus : a sermon preached in Christ Church, Savannah, on Thursday, September 18th, 1862, being the day set forth by the president of the Confederate States, as a day of prayer and thanksgiving, for our manifold victories, and especially for the fields of Manassas and Richmond, Ky.. 1862. Civil War Imprints. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/1741rn8t6k-cor.
APA, 6th edition
Elliott, Stephen, 1806-1866. (1862)[Our cause in harmony with the purposes of God in Christ Jesus : a sermon preached in Christ Church, Savannah, on Thursday, September 18th, 1862, being the day set forth by the president of the Confederate States, as a day of prayer and thanksgiving, for our manifold victories, and especially for the fields of Manassas and Richmond, Ky.]. Civil War Imprints, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/1741rn8t6k-cor.
Chicago
Elliott, Stephen, 1806-1866, Our cause in harmony with the purposes of God in Christ Jesus : a sermon preached in Christ Church, Savannah, on Thursday, September 18th, 1862, being the day set forth by the president of the Confederate States, as a day of prayer and thanksgiving, for our manifold victories, and especially for the fields of Manassas and Richmond, Ky., 1862, Civil War Imprints, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/1741rn8t6k-cor.