Nolan Ryan, Skip Bayless, Tom House (1991). “Nolan Ryan's Pitcher's Bible: The Ultimate Guide to Power, Precision, and Long-Term Performance”, p.30, Simon and Schuster
Gary Hamel (2012). “What Matters Now: How to Win in a World of Relentless Change, Ferocious Competition, and Unstoppable Innovation”, p.139, John Wiley & Sons
Mahatma Gandhi, Jawaharlal Nehru, Rabindranath Tagore (1968). “Wit and Wisdom of Gandhi, Nehru, Tagore: Being a Treasury of Over Ten Thousand Invaluable and Inspiring Thoughts, Views, and Obervations on about Eight Hundred Subjects of Popular Interest, Collected from the Speeches and Writings of These Three Great Leaders of Modern India”
Nolan Ryan, Skip Bayless, Tom House (1991). “Nolan Ryan's Pitcher's Bible: The Ultimate Guide to Power, Precision, and Long-Term Performance”, p.30, Simon and Schuster