TY  - SER
AU  - Ouwerkerk, C. Van,
TI  - Soil and Tillage Research Vol. 1(1), Vol. 6(2-4)
U1  - 631.5105 
PY  - 1980///,85-86
CY  - Netherlands
PB  - International Soil Tillage Research Organization
KW  - Soil Tillage Research
ER  -