1. Lect Notes Comput Sci;X. Lai,1991
2. X. Lai, J. L. Massey and S. Murphy “Markov ciphers and di.erential cryptanalysis”, Advances in Cryptology-EUROCRYPT 91, pp. 17–38.
3. A.J. Menezes, PC. van Oorschot, S.A. Vanstone: “Handbook of Applied Cryptography”, CRC Press Ltd., 1997, pp. 263–266.
4. Lect Notes Comput Sci;H. Lipmaa,1999
5. S.L.C. Salomão, J.M.S. Alcântara, V.C. Alves, F.M.G Franca: “Improved IDEA”, Proceedings of the 13th Brazilian Symposium on Integrated Circuits and System Design-SBCCI 2000, September 2000, Manaus, Brazil, pp. 47–52.