J. Robert Oppenheimer's letter to his brother Frank Oppenheimer (October 14, 1929), as quoted in "Robert Oppenheimer: Letters and Recollections" edited by Alice Kimball Smith (p. 136), 1995.
Paul Pearsall (2009). “Last Self-Help Book You'll Ever Need: Repress Your Anger, Think Negatively, be a Good Blamer and Throttle Your Inner Child”, p.45, Basic Books