Brian Tracy (2008). “Eat That Frog!: 21 Great Ways to Stop Procrastinating and Get More Done in Less Time: Easyread Super Large 20pt Edition”, p.5, ReadHowYouWant.com
Benjamin Franklin, William-Temple Franklin (1818). “Memoirs of the Life and Writings of (the Same), Continued to the Time of His Death by William Temple Franklin. - London, H. Colburn 1818”, p.68
"Great American Lives: The Autobiography of Benjamin Franklin, Personal Memoirs of Ulysses S. Grant, Autobiography of Andrew Carnegie, and The Education of Henry Adams".