Mollin, Richard A. <br/><br/>
Codes:  the guide to secrecy from ancient to modern times / 
Richard A. Mollin 
 - Boca Raton :  Chapman & Hall/CRC,  2005 
 - 679 p. :  ill. ;  24 cm. 
 - Discrete mathematics and its applications .
<br/><br/><label>ISBN: </label>1584884703 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Computer security<br/>Data encryption (Computer science)