TY  - BOOK
AU  - Gilliom,Robert J.
AU  - Thelin,Gail P.
ED  - National Water Quality Assessment Program (U.S.)
ED  - U.S. Geological Survey
TI  - Classification and mapping of agricultural land for national water-quality assessment
PY  - 1997///
CY  - Washington, Denver, Colo.
PB  - U.S. G.P.O., Free on application to the U.S. Geological Survey, Information Services
KW  - Agricultural mapping
KW  - United States
KW  - Land use, Rural
KW  - Water quality
N1  - 'National Water-Quality Assessment Program.'; Includes bibliographical references (p. 30)
ER  -