William Goldman (2013). “The Princess Bride: An Illustrated Edition of S. Morgenstern's Classic Tale of True Love and High Adventure”, p.298, Houghton Mifflin Harcourt
Gary Hamel (2012). “What Matters Now: How to Win in a World of Relentless Change, Ferocious Competition, and Unstoppable Innovation”, p.99, John Wiley & Sons