"Remembering Sam Shepard: The Pulitzer-Winning Playwright and Author's 10 Best Quotes on Writing, Love and Life" by Olivia Ladd, parade.com. July 31, 2017.
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.161