Mercy Otis Warren (1805). “History of the Rise, Progress and Termination of the American Revolution: Interspersed with Biographical, Political and Moral Observations. In Three Volumes”, p.316
Thomas Bulfinch (1858). “The Age of Chivalry: Or Legends of King Arthur, "King Arthur and His Knights", "The Mabinogeon", "The Crusades", "Robin Hood", Etc”, p.196