Date of this Version
Postulated Evolution of Platte River and Related Drainages: Souders, V. L., Swinehart, J. B., Dreeszen, V. H. (na; 1990), size 8.5" x 11". Description: The following four maps of Nebraska are shown: Late Pliocene; Early Pleistocene; Illinoian; and Late Wisconsin. A USGS publication (MAP-I-1420).