Kaplansky, Irving. <br/><br/>
Fields and Rings /  

 - Second Ed. /  
 - Chicago :   University of Chicago Press ,   1972 
 - p.206 :  
<br/><br/><label>ISBN: </label>0-226-42450-2 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Rings
<br/><br/><label>Dewey Class. No.: </label>B25  / K5,L2K