TY  - BOOK
AU  - H S SINGH , I G N F A
TI  - PRINCIPLES OF ENVIRONMENTAL CONSERVATION
SN  - 8770891019
U1  - TR 639.9 SI 64 
PY  - 1989///
CY  - DEHRADUN
PB  - INTERNATIONAL BOOK DISTRIBUTION
KW  - INTERNATIONAL BOOK DISTRIBUTION
N1  - MODERN BOOK HOUSE
ER  -