TY  - BOOK
AU  - Gillion,Robert J.
AU  - Thelin,Gail P.
ED  - United States.
ED  - United States
TI  - Classification and mapping of agricultural land for national water-quality assessment
SN  - 0607868090
U1  - 333.760973 
PY  - 1997///].
CY  - United Stated: 
PB  - U. S. Department of the Interior, , U. S. Geological Survey
KW  - Agricultural mapping
KW  - United States
KW  - Land use, Rular
KW  - Water quality
N1  - Includes bibliographical references (p. 30)
ER  -