Walker, C. B. (1879). The Mississippi Valley and prehistoric events: Giving an account of the original formation and early condition of the great valley; of its vegetable and animal life; of its first inhabitants, the mound builders, its mineral treasures and agricultural developments; all from authentic sources. Burlington, Iowa: R. T. Root.

Walker, C. B. The Mississippi Valley and Prehistoric Events: Giving an Account of the Original Formation and Early Condition of the Great Valley; of Its Vegetable and Animal Life; of Its First Inhabitants, the Mound Builders, Its Mineral Treasures and Agricultural Developments; All From Authentic Sources. Burlington, Iowa: R. T. Root, 1879.

Walker, C. B. The Mississippi Valley and Prehistoric Events: Giving an Account of the Original Formation and Early Condition of the Great Valley; of Its Vegetable and Animal Life; of Its First Inhabitants, the Mound Builders, Its Mineral Treasures and Agricultural Developments; All From Authentic Sources. Burlington, Iowa: R. T. Root, 1879.