Kent, Allen. <br/><br/>
Encyclopedia of Library and Information Science Vol-17 /  

 - First Ed. /  
 - New York-10016 :   Marcel Dekker, Inc.. 
 - p.508 :  
<br/><br/><label>ISBN: </label>0-8247-2017-2 
<br/><br/><label>Dewey Class. No.: </label>2K  / K8.17