Massachusetts Historical Society, John Adams, Samuel Adams, James Warren (1917). “Warren-Adams Letters: Being Chiefly a Correspondence Among John Adams, Samuel Adams, and James Warren ... 1743-1814”
Entry for March 9, 1774. "The History of the Rise, Progress, and Establishment, of the Independence of the United States of America". Book by William Gordon, Volume 1 p. 347, 1969.