1. D.O. Smith, K.J. Harte: IEEE Trans. EC-15, 123 (1966)
2. D.O. Smith, K.J. Harte: IEEE Trans. EC-16, 372 (1967)
3. K.Y. Ahn, Y.S. Lin: IBM Tech. Discl. Bull. 15, 2017 (1972)
4. T. Kohonen: Content-Addressable Memories, 2nd. ed., Springer Ser. Inform. Sci. Vol. 1 ( Springer, Berlin, Heidelberg 1987 )
5. D.H. Casier: IBM Tech. Disci. Bull. 16, 217 (1973)