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3. See for example, Foundations and Applications of Cluster Variation Method and Path Probability Method, edited by T. Morita, M. Suzuki, K. Wada, and M. Kaburagi, Progr. Theor. Phys. Suppl. 113 (1994).
4. K. Fukunaga, Introduction to Statistical Pttern Recognition, (Academic Press, New York, 1972).
5. T. Geszti, Physical Models of Neural Network, (World Scientfìc, Singapore, 1990).