TY  - BOOK
AU  - Verma, P. S.
AU  - Agarwal, V. K.
TI  - Rinciples of ecology: : environmental biology
U1  - 577 
PY  - 1986///
CY  - New Delhi
PB  - S. Chand
KW  - Biology
N1  - Includes index
ER  -