1. Machine-readable files developed for the High Plains Regional Aquifer-System analysis in parts of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming Author/Creator: Ferrigno, Carmelo F., author Publication/Creation: Denver, Colorado : U.S. Geological Survey, 1986 Resource Type: Book Access & Availability: Loading
2. Major geochemical processes related to the hydrology of the Madison aquifer system and associated rocks in parts of Montana, South Dakota, and Wyoming Author/Creator: Busby, John F., author Publication/Creation: Denver, Colorado : U.S. Geological Survey, 1983 Resource Type: Book Access & Availability: Loading