The Flatey Book and Recently Discovered Vatican Manuscripts Concerning America as Early as the Tenth Century: Documents Now Published for the First Time, which Establish Beyond Controversy the Claim that North America was Settled by Norsemen Five Hundred Years Before the Time of Columbus. Sagas that Describe the Voyages To, and Character Of, the New Country, and Letters from Several Popes Directing Bishops in Their Government of the Church in the Western World