%0 Journal Article %A Havrda, Jan %A Charvát, František %T Quantification method of classification processes. Concept of structural $a$-entropy %J Kybernetika %D 1967 %P 30-35 %V 3 %N 1 %U http://geodesic.mathdoc.fr/item/KYB_1967_3_1_a2/ %G en %F KYB_1967_3_1_a2