Joseph Murphy (2009). “Putting the Power of Your Subconscious Mind to Work: Reach New Levels of Career Success Using the Power of Your Subconscious Mind”, p.181, Penguin
Joseph Murphy, Ph.D., D.D. (1986). “Your Infinite Power to be Rich: Use the Power of Your Subconscious Mind to Obtain the Prosperity You Deserve”, p.15, Penguin