TY  - BOOK
AU  - Welsh,Dominic
TI  - Codes and cryptography
SN  - 9780198532873 (pbk.)
U1  - 652.8 WEL 
PY  - 1998///
CY  - Oxford
PB  - Oxford University Press
KW  - Ciphers
KW  - Cryptography
ER  -