TY  - BOOK
AU  - K. N. Duggal
TI  - Elements of environmental engineering
SN  - 9788121915472
U1  - 628 
PY  - 1966///
CY  - New Delhi
PB  - S. Chand & Company Ltd.
KW  - Engineering -- Greece -- HistorySewage-Environmental aspects; Buildings-Environmental engineering; Environmental engineering
ER  -