Ground-water flow direction, water quality, recharge sources, and age, Great Sand Dunes National Monument, south-central Colorado, 2000-2001 / by Michael G. Rupert and L. Niel Plummer ; prepared in cooperation with the National Park Service. [electronic resource]
Imprint
Reston, Va. : U.S. Dept. of the Interior, U.S. Geological Survey ; Denver, CO : U.S. Geological Survey, Information Services [distributor], 2004.