Albert Einstein, Stephen W. Hawking (2007). “A Stubbornly Persistent Illusion: The Essential Scientific Works of Albert Einstein”, p.346, Running Press
Albert Einstein, Stephen W. Hawking (2007). “A Stubbornly Persistent Illusion: The Essential Scientific Works of Albert Einstein”, p.346, Running Press
Thomas Jefferson (1854). “The Writings of Thomas Jefferson: Inaugural addresses and messages. Replies to public addresses. Indian addresses. Miscellaneous: 1. Notes on Virginia; 2. Biographical sketches of distinguished men; 3. The batture of New Orleans”, p.400
Albert Einstein, Stephen W. Hawking (2007). “A Stubbornly Persistent Illusion: The Essential Scientific Works of Albert Einstein”, p.346, Running Press