TY  - BOOK
AU  - Havlin,John L et.al
TI  - Soil fertility and fertilizers: an introduction to nutrient management 
SN  - 9780135033739
U1  - 631.42 SOI 2014 
PY  - 2014///
CY  - Newyork
PB  - : Pearson 
N1  - Index
ER  -