TY  - BOOK
AU  - Asthana, D. K.
AU  - Asthana, Meera
TI  - A textbook of environmental studies: as per UGC model curriculum
SN  - 9788121927642
U1  -  363.7 
PY  - 2012///
CY  - New Delhi,India
PB  - S. Chand & Company Ltd.
ER  -