Henry David Thoreau (2014). “Citizen Thoreau: Walden, Civil Disobedience, Life Without Principle, Slavery in Massachusetts, A Plea for Captain John Brown”, p.210, Graphic Arts Books
Alexis de Tocqueville, François Furet, Francoise Melonio (1998). “The Old Regime and the Revolution, Volume I: The Complete Text”, p.222, University of Chicago Press