Letters of Albert Einstein
Einstein, Albert. "Letter to his son Eduard." Quoted in Einstein: His Life and Universe, by Walter Isaacson. Simon & Schuster, 2007. Originally from Letter to his Son Eduard, 5 Feb. 1930.
Einstein, Albert. "To Jost Winteler." The Collected Papers of Albert Einstein, vol. 1: The Early Years, 1879-1902, English Translation Supplement, translated by Anna Beck. Princeton University Press, 1987, no. 115. Originally from Letter to Jost Winteler, 8 July 1901.
Einstein, Albert. "Letter to Dr. H. L. Gordon." Quoted in Einstein: His Life and Universe, by Walter Isaacson. Simon & Schuster, 2007. Originally from Letter to Dr. H. L. Gordon, 3 May 1949.
Einstein, Albert. Quoted in Einstein and Religion: Physics and Theology, by Max Jammer. Princeton University Press, 1999. Originally from Letter to Michaelangelo Besso, 21 Mar. 1955.
Einstein, Albert. Quoted in Einstein on Peace, edited by Otto Nathan and Heinz Norden. Simon and Schuster, 1960, ch. 9. Originally from Letter to Franklin Roosevelt, 2 Aug. 1939.