Theodore Roosevelt (2015). “Theodore Roosevelt on Bravery: Lessons from the Most Courageous Leader of the Twentieth Century”, p.4, Skyhorse Publishing, Inc.
Cathy Hopkins (2009). “Friend Me: Mates, Dates, and Inflatable Bras; Mates, Dates, and Cosmic Kisses; Mates, Dates, and Designer Divas”, p.24, Simon and Schuster
Address at the Sorbonne, Paris, 23 Apr. 1910. Richard M. Nixon quoted this passage in his address to the nation announcing his decision to resign the presidency, 8 Aug. 1974. See Theodore Roosevelt 1; Theodore Roosevelt 2; Theodore Roosevelt 5
Peter Marshall (1949). “Prayers Offered by the Chaplain, the Rev. Peter Marshall, D.D.: At the Opening of the Daily Sessions of the Senate of the United States During the Eightieth and Eighty-first Congress 1947-1949”