TY  - BOOK
AU  - Verma, P.S.
AU  - Agarwall, V.K.
TI  - Principles of ecology = environmental biology
U1  - 577 
PY  - 1989///
CY  - New Delhi
PB  - S. Chand, 
KW  - Ecology
KW  - Environmental aspects
N1  - [Includes glossary, bibliographies and index]
ER  -