TY  - BOOK
AU  - Roy,R.N.
TI  - Assessment of soil nutrient balance : : approaches and methodologie s / 
SN  - 9251050384
PY  - 2003///
CY  - Rome : 
PB  - FAO Publishing , 
KW  - Soils
KW  - Nitrate content
KW  - Nutrient cycles
N1  -  Includes bibliographical references (p.83-87)
ER  -