Kahn, David,  1930- <br/><br/>
The codebreakers :  the story of secret writing / 
David Kahn. 
 - Revised and updated. 
 - xviii, 1181 pages :  illustrations ;  25 cm 
<br/><br/> "Revised and Updated"--Cover. 
<br/><br/><label>ISBN: </label>0684831309 9780684831305 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Cryptography--History.
<br/><br/><label>Dewey Class. No.: </label>652