United States. President (1837-1841 : Van Buren), Martin Van Buren (1838). “Message from the President of the United States to the Two Houses of Congress: At the Commencement of the Third Session of the Twenty-fifth Congress”, p.17
Hunter S. Thompson's note to his grandson Will (2005), as quoted in William McKeen "Outlaw Journalist: The Life and Times of Hunter S. Thompson", 2008.