Humphreys,J,F. <br/><br/>
Numbers,Groups and Codes 
/ by J,F Humphreys 
 - new york  cambridge university press  1989 
 - xvi,288p. 
<br/><br/><label>ISBN: </label>000 
<br/><br/><label>Dewey Class. No.: </label>512.22  / HUM/N