Were all unique. 

 - Quezon City:   Hardware Zone Phils. Corp.,   c2015.  
 - pages 84-85;  30 cm.  
<br/><br/> HWM Philippines. 
<br/><br/><label>ISSN: </label>16565649  
<br/><br/><label>Subjects--Topical Terms: </label><br/>Ciphers
<br/><br/><label>Dewey Class. No.: </label>DPer 303.405 May-Sept 2015 no. 6-10