Yvon Chouinard (2016). “Let My People Go Surfing: The Education of a Reluctant Businessman--Including 10 More Years of Business Unusual”, p.90, Penguin
H. Jackson Brown Jr. (2007). “Complete Life's Little Instruction Book: 1,560 Suggestions, Observations, and Reminders on How to Live a Happy and Rewarding Life”, p.174, Thomas Nelson Inc
Yvon Chouinard (2016). “Let My People Go Surfing: The Education of a Reluctant Businessman--Including 10 More Years of Business Unusual”, p.96, Penguin