Air and water pollution. 

 - 215 pages ;  24 cm 
<br/><br/><label>LCCN: </label>57059144  
<br/><br/><label>Subjects--Topical Terms: </label><br/>Air--Pollution<br/>Water--Pollution
<br/><br/><label>LC Class. No.: </label>TD420  / .O74 1957