Okun, Daniel A. <br/><br/>
Community wasterwater collection and disposal   
by Daniel A. Okun and George Ponghis 
 - Geneva  World Health Organization  1975 
 - xii, 287p. 
<br/><br/><label>ISBN: </label>92 4 156045 2 
<br/><br/><label>Dewey Class. No.: </label>628.3  / N751