TY  - BOOK
AU  - Heady, Earl O. Vocke Gary F.
TI  - Economic models of agricultural land conservation and environmental improvement  
SN  - 813805236
PY  - 1992///
CY  - Ames, Iowa
PB  - Lowa State University Press
KW  - Soil FertilitySoil ImprovementSoil Sciences
ER  -