Brown, Dan. <br/><br/>
Digital Fortress / 
Dan Brown. 
 - [S.l.] :  Transworld Paperbacks,  2004 
 - 512 p. ;  18 cm. 
<br/><br/> When the NSA's invincible code-breaking machine - encounters a mysterious code it cannot break, the agency calls in its head cryptographer, Susan Fletcher, a brilliant and beautiful mathematician. What she uncovers sends shock waves through the corridors of power. The NSA is being held hostage...not by guns or bombs, but by a code so ingeniously complex that if released it will cripple U.S. intelligence. 
<br/><br/><label>ISBN: </label>0552151696 (paperback) 9780552151696 (paperback) 
<br/><br/><label>Dewey Class. No.: </label>813.54  / BRO-D