MLA
Andrew, James O. (James Osgood), 1794-1871. Letter from James O. Andrews (Oxford, Georgia) to Robert Paine - June 1, 1849. June 1, 1849. Robert Paine Papers, 1828-1882. Pitts Theology Library. https://digital.library.emory.edu/purl/9182jm6540-cor.
APA, 6th edition
Andrew, James O. (James Osgood), 1794-1871. (June 1, 1849)[Letter from James O. Andrews (Oxford, Georgia) to Robert Paine - June 1, 1849]. Robert Paine Papers, 1828-1882, Pitts Theology Library. https://digital.library.emory.edu/purl/9182jm6540-cor.
Chicago
Andrew, James O. (James Osgood), 1794-1871, Letter from James O. Andrews (Oxford, Georgia) to Robert Paine - June 1, 1849, June 1, 1849, Robert Paine Papers, 1828-1882, Pitts Theology Library. https://digital.library.emory.edu/purl/9182jm6540-cor.