Polk, James K. (1910). “The diary of James K. Polk during his presidency, 1845 to 1849, now first printed from the original manuscript in the collections of the Chicago historical society; Volume 4”, p.261, Best Books on
Martin Van Buren (2009). “Messages and Papers of the Presidents: Martin Van Buren, William Henry Harrison, John Tyler, James K. Polk”, p.1829, Wildside Press LLC