TY  - BOOK
AU  - Verma P. S. ,
AU  - Agarwal V. K.,
TI  - Environmental Biology Principles of Ecology: Environmentl Biology
SN  - 8121908590
U1  - 574.5 
PY  - 2014///
CY  - New Delhi
PB  - S. Chand and Co.
ER  -