TY  - BOOK
AU  - Verma,P S.
AU  - Agarwal,V K.
TI  - Environmental biology: principles of ecology 
SN  - 8121908590
U1  - 577 22
PY  - 1983///
CY  - New Delhi
PB  - Chand
KW  - Biology
KW  - Ecology
N1  - Includes bibliographical references and index
ER  -