1. Nitrate in the Columbia aquifer, central Delmarva Peninsula, Maryland Author/Creator: Bachman, L. Joseph, author Publication/Creation: Towson, Maryland : U.S. Geological Survey, 1984 Format: Book Access & Availability: Loading
2. Nitrogen, sulfate, chloride, and manganese in ground water in the alluvial deposits of the South Platte River Valley near Greeley, Weld County, Colorado Author/Creator: Geological Survey (U.S.), cartographer Publication/Creation: Denver, Colorado : Open-File Services Section, Western Distribution Branch, U.S. Geological Survey Format: Map Access & Availability: Loading
3. Numerical simulation of the high plains regional aquifer, northwestern Oklahoma Author/Creator: Havens, John S., author Publication/Creation: Oklahoma City, Oklahoma : U.S. Geological Survey, 1984 Format: Book Access & Availability: Loading