TY  - BOOK
AU  - Sandstra, H. G.
TI  - A methodology for on-farm cropping systems research
U1  - 631.5 
PY  - 1981///
CY  - Manila
PB  - International Rice Research Institute
KW  - Agricultura
KW  - Investigacion
KW  - Asia
KW  - Sistemas de cultivo
ER  -