LEADER 00000nam  2200000 a 4500 
001    959939153 
003    OCoLC 
008    050425r20001999enk 00  0 eng 0     eng   
020    9781857028898 
020    1857028899 
050    Z104|b.S56 2000 
100 1  Singh,Simon.  
245 10  The code book:|bthe secret history of codes and code-
       breaking/|csimon singh. 
260    london;|bfourth state,|c2000. 
300    xiii,402 pages;|billustrations,|c20 cm 
504    Originally published: 1999. 
650 0  Cryptography|xHistory    
650 0  Data encryption (Computer science)|xHistory