Hopkins, Edward S. <br/><br/>
Water purification control / 
Edward S. Hopkins. 
 - 3rd ed. 
 - Maltimore :  the williams & Wilkings,  c 1948. 
 - vii, 289 p. :  ill. ;  20 cm. 
<br/><br/> Includes  Index.<br/> 
<br/><br/>323  323 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Water--Purification.<br/>Water--Analysis.
<br/><br/><label>Dewey Class. No.: </label>628.1 / H774w