Mark Twain (2014). “Mark Twain on Common Sense: Timeless Advice and Words of Wisdom from America's Most-Revered Humorist”, p.17, Skyhorse Publishing, Inc.
William Lloyd Garrison (1832). “Thoughts on African Colonization: Or an Impartial Exhibition of the Doctrines, Principles and Purposes of the American Colonization Society. Together with the Resolutions, Addresses and Remonstrances of the Free People of Color”, p.6