TY  - BOOK
AU  - Chopra V L 
AU  - Singh, R B 
AU  - Anupam Varma 
TI  - Crop Productivity and Sustainability: shaping the future 
T2  - Proceedings of 2nd International Crop Science Congress 
SN  - 8120412125
U1  - 631 
PY  - 1998///
CY  - New Delhi 
PB  - Oxford & IBH 
ER  -