Lewis, W. G. (2010). In the footsteps of Lewis and Clark: Early commemorations and the origins of the national historic trail. University Press of Colorado.

Lewis, Wallace G. In the Footsteps of Lewis and Clark: Early Commemorations and the Origins of the National Historic Trail. Boulder: University Press of Colorado, 2010.

Lewis, Wallace G. In the Footsteps of Lewis and Clark: Early Commemorations and the Origins of the National Historic Trail. University Press of Colorado, 2010.