Appropriate technology for water supply and sanitation 
/ Transportation, Water and Telecommunication Department, December 1980 
 - USA:    Transportation, Water and Telecommunication Department,    1980 
<br/><br/> Vol.5 <br/>Vol.11<br/>Vol.1b 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Science
<br/><br/><label>Subjects--Index Terms: </label>Environment  
<br/><br/><label>Universal Decimal Class. No.: </label>628.3/4:301.15  / M0