Conversation with George Sewall Boutwell concerning the nomination of Salmon P. Chase to the U.S. Supreme Court, reported by Boutwell in his "Reminiscences of Sixty Years in Public Affairs", vol. 2, (p. 29), 1902.
Abraham Lincoln, Archer Hayes Shaw (1980). “The Lincoln encyclopedia: the spoken and written words of A. Lincoln arranged for ready reference”, Greenwood Pub Group
Abraham Lincoln, Don Edward Fehrenbacher (1977). “Abraham Lincoln, a Documentary Portrait Through His Speeches and Writings”, p.39, Stanford University Press