TY  - BOOK
AU  - Sparks, Donald L
TI  - Advances in agronomy V.77, 2002
SN  - 0120007959
U1  - 631/635 
PY  - 2002///
CY  - Amsterdam
PB  - Academic Press
KW  - Micronutrients
KW  - Organic farming
ER  -