TY  - BOOK
AU  - VERMA (P S)
AU  - AGARWAL (V K).
TI  - Concepts of ecology: environmental biology
SN  - 81 219 1681 X
U1  - 574.5 VERC 
PY  - 1999///
CY  - ND
PB  - S. Chand & Co. Ltd.
KW  - Ecology environmental biology
ER  -