Helferich, Friedrich <br/><br/>
Ion exchange / 
Friedrich Helferic. 
 - New York :  McGraw-Hill Book Co., Inc.,  1962. 
 - ix, 624 p.  ill. 
<br/><br/>Includes bibliogr. references 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Ion exchange