TY - JOUR AU - Karásek, Jiří TI - Projections of relations JO - Mathematica Bohemica PY - 1995 SP - 283 EP - 291 VL - 120 IS - 3 PB - mathdoc UR - http://geodesic.mathdoc.fr/articles/10.21136/MB.1995.126001/ DO - 10.21136/MB.1995.126001 LA - en ID - 10_21136_MB_1995_126001 ER -