Marcus Tullius Cicero (1856). “Cicero's Three Books Of Offices, Or Moral Duties: Also His Cato Major, an Essay on Old Age; Laelius, an Essay on Friendship; Paradoxes; Scipio's Dream; and Letter to Quintus on the Duties of a Magistrate”, p.206
Ralph Cudworth, Thomas Birch (1838). “The True Intellectual System of the Universe: Wherein All the Reason and Philosophy of Atheism is Confuted, and Its Impossibility Demonstrated. A Treatise on Immutable Morality; with a Discourse Concerning the True Notion of the Lord's Supper: and Two Sermons on 1. John 2: 3, 4, and 1. Cor. 15: 27”, p.577
"The History of Freedom in Antiquity". Lord Acton's opening statement of his speech on February 28, 1877; later quoted in "The History of Freedom and Other Essays" edited by John Neville Figgis and Reginald Vere Laurence, 1907.