TY  - BOOK
AU  - Verma, P.S.
AU  - Verma, P.S.
TI  - Environmental biology : principles of ecology
SN  - 81-219-0859-0
U1  - 577 VEE 22
PY  - 2001///
CY  - New Delhi
PB  - S.Chand and Company.
KW  -  
KW  - Environmental biology
ER  -