Albert Einstein's speech made in honor of Thomas Mann, when Mann was given the Einstein Prize given by the Jewish Forum (January 1939), as quoted in Abraham Pais "Einstein Lived Here" (p. 214), 1994.
Robert Louis Stevenson (2015). “Collected Memoirs, Travel Sketches and Island Literature of Robert Louis Stevenson: Autobiographical Writings and Essays by the prolific Scottish novelist, poet and travel writer, author of Treasure Island, The Strange Case of Dr. Jekyll and Mr. Hyde, Kidnapped & Catriona”, p.288, e-artnow
Stephen R. Covey (1994). “Daily Reflections for Highly Effective People: Living THE SEVEN HABITS OF HIGHLY SUCCESSFUL PEOPLE Every Day”, p.31, Simon and Schuster