MLA
Wesley, John, 1703-1791. Letter from John Wesley to George Baldwin, Kingswood - March 14, 1789. 1931. Wesleyana Collection. Pitts Theology Library. https://digital.library.emory.edu/purl/078gf1vj1b-cor.
APA, 6th edition
Wesley, John, 1703-1791. (1931)[Letter from John Wesley to George Baldwin, Kingswood - March 14, 1789]. Wesleyana Collection, Pitts Theology Library. https://digital.library.emory.edu/purl/078gf1vj1b-cor.
Chicago
Wesley, John, 1703-1791, Letter from John Wesley to George Baldwin, Kingswood - March 14, 1789, 1931, Wesleyana Collection, Pitts Theology Library. https://digital.library.emory.edu/purl/078gf1vj1b-cor.