%0 Journal Article %A Zabczyk, Jerzy %T A mathematical correction problem %J Kybernetika %D 1972 %P 317-322 %V 8 %N 4 %U http://geodesic.mathdoc.fr/item/KYB_1972_8_4_a3/ %G en %F KYB_1972_8_4_a3