Walter Lippmann, Clinton Rossiter, James Lare (1982). “The Essential Lippmann: A Political Philosophy for Liberal Democracy”, p.182, Harvard University Press
Philip Dormer Stanhope (4th earl of Chesterfield.), Charles Caleb Colton (1861). “Lord Chesterfield's advice to his son on men and manners. To which are added, selections from Colton's 'Lacon'.”, p.246