Malam, John <br/><br/>
Crack the code  

 - Oxford    Oxford University Press  2009 
<br/><br/><label>ISBN: </label>978 0 19 847590 3 
<br/><br/><label>Subjects--Topical Terms: </label><br/>CRYPTOGRAPHY JUVENILE LITERATURE
<br/><br/><label>Dewey Class. No.: </label>J428 64024 MAL