%0 Journal Article %T Zprávy %J Applications of Mathematics %D 1960 %P 156-158 %V 05 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.21136/AM.1960.102701/ %R 10.21136/AM.1960.102701 %G cz %F 10_21136_AM_1960_102701