MLA
Andrew, James O. (James Osgood), 1794-1871. Letter from James O. Andrews (Oxford, Georgia) to Robert Paine - March 25, 1852. March 25, 1852. Robert Paine Papers, 1828-1882. Pitts Theology Library. https://digital.library.emory.edu/purl/238w9ghz7s-cor.
APA, 6th edition
Andrew, James O. (James Osgood), 1794-1871. (March 25, 1852)[Letter from James O. Andrews (Oxford, Georgia) to Robert Paine - March 25, 1852]. Robert Paine Papers, 1828-1882, Pitts Theology Library. https://digital.library.emory.edu/purl/238w9ghz7s-cor.
Chicago
Andrew, James O. (James Osgood), 1794-1871, Letter from James O. Andrews (Oxford, Georgia) to Robert Paine - March 25, 1852, March 25, 1852, Robert Paine Papers, 1828-1882, Pitts Theology Library. https://digital.library.emory.edu/purl/238w9ghz7s-cor.