Letter from the field of Waterloo in June 1815. "The Fifteen Decisive Battles of the World: From Marathon to Waterloo" by Edward Shepherd Creasy, 1851.
Arthur Wellesley, Duke of Wellington (2012). “Maxims and Opinions of Field-Marshal His Grace the Duke of Wellington, Selected From His Writings and Speeches During a Public Life of More Than Half a Century”, p.377, tredition
Quoted in Philip Henry Stanhope, Notes of Conversations with the Duke of Wellington (1888) (entry for 3 Nov. 1831) See Francis Bacon 7; Montaigne 4; Franklin Roosevelt 6; Thoreau 16
Dispatch to Torrens, 29 August 1810 (usually quoted as 'I don't know what effect these men will have upon the enemy, but, by God, they frighten me', and also attributed to George III)