Crystal , David. <br/><br/>
Cambridge factfinder  

 - 4th edition. 
 - New York :  Cambridge University,  1994 
 - 938. 
<br/><br/><label>ISBN: </label>0521794358  
<br/><br/><label>Subjects--Topical Terms: </label><br/>Knowledge
<br/><br/><label>Dewey Class. No.: </label>001  / CRY