Benjamin Franklin, Edmund Sears Morgan (2007). “Not Your Usual Founding Father: Selected Readings from Benjamin Franklin”, p.119, Yale University Press
Frederick Douglass (2017). “FREDERICK DOUGLASS, AN AMERICAN SLAVE – Astounding Life of One Incredible Man (3 Autobiographies in One Volume): The Most Important African American Leader of the 19th Century: The Escape from Slavery, Life as a World-Renowned Activist against Slavery and Racism & Political Career after the Civil War”, p.740, e-artnow