Albert Einstein (2016). “The Albert Einstein Collection: Essays in Humanism, The Theory of Relativity, and The World As I See It”, p.117, Open Road Media

Quoted in Alexander Macfarlane, Ten British Mathematicians of the Nineteenth Century (1916). "Pure mathematics; may it never be of use to any man!" is cited as the toast of the Mathematical Society of England in Science, 10 Dec. 1886.

Albert Einstein (2015). “Bite-Size Einstein: Quotations on Just About Everything from the Greatest Mind of the Twentieth Century”, p.24, St. Martin's Press

Albert Einstein (2015). “Bite-Size Einstein: Quotations on Just About Everything from the Greatest Mind of the Twentieth Century”, p.32, St. Martin's Press

Albert Einstein (2015). “Bite-Size Einstein: Quotations on Just About Everything from the Greatest Mind of the Twentieth Century”, p.31, St. Martin's Press