Mann, H. T. <br/><br/>
Water treatment and sanitation  A Handbook of simple methods for rural areas in developing countries 
by H. T. Mann and Williamson, D. 
 - 2nd rev. 
 - London  Intermediate Technology  1979 
 - 92p. 
<br/><br/><label>ISBN: </label>0 903031 23 X 
<br/><br/><label>Dewey Class. No.: </label>628.16  / N79