TY  - SER
AU  - Sparks, D L,
TI  - Advances in Agronomy Vol.66
SN  - 0120007665
U1  - 630 
PY  - 1999///
CY  - SanDiego
PB  - Academic Press
KW  - Agriculture. & related technologies
KW  - Agronomy
ER  -