Duggal, k.n <br/><br/>
Elements of environmental engineering 

 - New Delhi  S. Chand and Company LTD.  c1966 
 - xv,440p  ill.; 
<br/><br/><label>ISBN: </label>9788121915472 
<br/><br/><label>LC Class. No.: </label>TA170  / DUG