TY  - BOOK
AU  - S. S. Purohit, Q.J. Shammi and A.K. Agrawal
TI  - A text book of environment sciences
SN  - 978-8177542103
U1  - 363.7 
PY  - 2004///
CY  - Student Education , New Delhi 
PB  - Student Education , New Delhi 
KW  -  Environmental Science
ER  -