000 00269nam a22001217a 4500
999 _c33819
_d33819
020 _a8121927927
082 _a620.8
100 _aDuggal,K.N.
245 _aElements of Environmental Engineering
260 _aNew Delhi
_bS.chand
_c2008
300 _a440 p.
942 _cBK