by G.N. Delin ... [and others] ; prepared in cooperation with the University of Minnesota Department of Soil Science, the U.S. Department of Agriculture, Agricultural Research Service, and the Minnesota Pollution Control Agency
by Michael J. Focazio ... [and others] ; prepared in cooperation with the U.S. Environmental Protection Agency, Office of Ground Water and Drinking Water
by Michael J. Focazio ... [and others] ; prepared in cooperation with the U.S. Environmental Protection Agency, Office of Ground Water and Drinking Water
by Edward J. Koszalka ... [and others] ; prepared by the U.S. Geological Survey in cooperation with the New York State Department of Environmental Conservation