Michel de Montaigne (1853). “The Works of Michael de Montaigne: Comprising His Essays, Letters, and Journey Through Germany and Italy. With Notes from All the Commentators, Biographical and Bibliographical Notices &c., &c”, p.2
David J. Lieberman (2010). “Find Out Who's Normal and Who's Not: The Proven System to Quickly Assess Anyone's Emotional Stability”, p.161, David Lieberman