1. Percentile distributions of median nitrite plus nitrate as nitrogen, total nitrogen, and total phosphorus concentrations in Oklahoma streams, 1973-2001 Author/Creator: Haggard, Brian E. (Brian Edward) Publication/Creation: Oklahoma City, OK : U.S. Dept. of the Interior, U.S. Geological Survey, 2003 Resource Type: Book Access & Availability: Loading
2. Possible sources of nitrate in ground water at swine licensed-managed feeding operations in Oklahoma, 2001 Author/Creator: Becker, Mark F. Publication/Creation: [Reston, Va.?] : U.S. Dept. of the Interior, U.S. Geological Survey, 2003 Resource Type: Book Edition: Revised Jan. 2003. Access & Availability: Loading
3. Possible sources of nitrate in ground water at swine licensed-managed feeding operations in Oklahoma, 2001 Author/Creator: Becker, Mark F. Publication/Creation: Oklahoma City, OK : U.S. Dept. of the Interior, U.S. Geological Survey, [2002] Resource Type: Book Access & Availability: Loading