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2. H. C. vanTilborg, An Introduction to Cryptology. Kluwer Academic Publishers, 1988.
3. C. Shannon, “Communication Theory and Secrecy Systems”, Bell System Technical Journal, vol. 28, pp. 656–715, Oct 1949.
4. D. R. Stinson, Cryptography: Theory and Practice. CRC Press, 1995.
5. A. Menezes, P. vanOorschot, and S. Vanstone, Handbook of Applied Cryptography. CRC Press, 1997.