Zebulon Montgomery Pike, Thomas Rees (1811). “Exploratory Travels Through the Western Territories of North America: Comprising a Voyage from St. Louis, on the Mississippi, to the Source of that River, and a Journey Through the Interior of Louisiana, and the North-eastern Provinces of New Spain ; Performed in the Years 1805, 1806, 1807, by Order of the Government of the United States”, p.268