Khan, David. <br/><br/>
How I discovered World War II's greatest spy: And other stories of intelligence and code 
by David Kahn 
 - New York  CRC Press  2013 
 - xiv, 475p. 
<br/><br/><label>ISBN: </label>9781466561991 
<br/><br/><label>Dewey Class. No.: </label>940.5485  / P13