Horace Mann (1850). “A Few Thoughts for a Young Man: A Lecture, Delivered Before the Boston Mercantile Library Association, on Its 29th Anniversary”, p.38
Horace Mann (1849). “Speech of Hon. Horace Mann, of Massachusetts, on Slavery and the Slave-trade in the District of Columbia: Delivered in the House of Representatives of the United States, February 23, 1849”, p.23