William Shakespeare (2013). “The Wars of the Roses In Plain and Simple English: Includes Henry VI Parts 1 - 3 & Richard III, Richard II, Henry IV Parts 1 and 2, and Henry V”, p.1174, BookCaps Study Guides
Edward Gibbon (2016). “THE HISTORY OF THE DECLINE AND FALL OF THE ROMAN EMPIRE (All 6 Volumes): From the Height of the Roman Empire, the Age of Trajan and the Antonines - to the Fall of Byzantium; Including a Review of the Crusades, and the State of Rome during the Middle Ages”, p.106, e-artnow