Plutarch (1957). “Plutarch's Moralia: Concerning the face which appears in the orb of the moon. On the principle of cold. Whether fire or water is more useful. Whether land or sea animals are cleverer. Beasts are rational. On the earing of flesh”
Henry David Thoreau (2014). “Citizen Thoreau: Walden, Civil Disobedience, Life Without Principle, Slavery in Massachusetts, A Plea for Captain John Brown”, p.131, Graphic Arts Books