%0 Journal Article %A Karásek, Jiří %T Projections of relations %J Mathematica Bohemica %D 1995 %P 283-291 %V 120 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.21136/MB.1995.126001/ %R 10.21136/MB.1995.126001 %G en %F 10_21136_MB_1995_126001