MLA
Elliott, Stephen, 1806-1866. "Samson's riddle" : a sermon preached in Christ Church, Savannah, on Friday, March 27th, 1863 : being the day of humiliation, fasting and prayer, appointed by the president of the Confederate States. 1863. Civil War Imprints. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/989r2283pg-cor.
APA, 6th edition
Elliott, Stephen, 1806-1866. (1863)["Samson's riddle" : a sermon preached in Christ Church, Savannah, on Friday, March 27th, 1863 : being the day of humiliation, fasting and prayer, appointed by the president of the Confederate States]. Civil War Imprints, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/989r2283pg-cor.
Chicago
Elliott, Stephen, 1806-1866, "Samson's riddle" : a sermon preached in Christ Church, Savannah, on Friday, March 27th, 1863 : being the day of humiliation, fasting and prayer, appointed by the president of the Confederate States, 1863, Civil War Imprints, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/989r2283pg-cor.