Gates Phil <br/><br/>
Codes and Signals 

 - United Kingdom  The Press Syndicate Of The University Of Cambridge  c1997 
 - 24p  ill;  25cm. 
<br/><br/> include index 
<br/><br/><label>ISBN: </label>0521778905 
<br/><br/><label>Dewey Class. No.: </label>302.23 GATE