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.108, e-artnow
James Madison (1836). “The Debates in the Several State Conventions on the Adoption of the Federal Constitution: As Recommended by the General Convention at Philadelphia in 1787. Together with the Journal of the Federal Convention, Luther Martin's Letter, Yates's Minutes, Congressional Opinions, Virginia and Kentucky Resolutions of '98-'99, and Other Illustrations of the Constitution”, p.95
"Putin speaks out on Ukraine, Crimea and US relations with French media". Interview with Gilles Bouleau and Jean-Pierre Elkabbach, www.rt.com. June 5, 2014.