TY  - SER
AU  - van Burg, P. F. J.,
TI  - Fertilizer Research Vol. 21(1-3), Vol. 22 (1-3)
U1  - 631 
PY  - 1989///-90
CY  - Dordrecht
PB  - Kluwer Academic Publishers
KW  - Fertilizers
KW  - Techniques, equipment & materials
ER  -