Horace Mann (1871). “A Few Thoughts for a Young Man: A Lecture, Delivered Before the Boston Mercantile Library Association, on Its Twenty-ninth Anniversary”, p.80
Massachusetts. Board of Education, Horace Mann (1849). “The Massachusetts System of Common Schools: Being an Enlarged and Rev. Ed of the Tenth Annual Report of the First Secretary of the Massachusetts Board of Education”, p.80
Horace Mann (1850). “A Few Thoughts for a Young Man: A Lecture, Delivered Before the Boston Mercantile Library Association, on Its 29th Anniversary”, p.70
Horace Mann (1850). “A Few Thoughts for a Young Man: A Lecture, Delivered Before the Boston Mercantile Library Association, on Its 29th Anniversary”, p.49