TY - JOUR AU - Chajda, Ivan TI - Weak homomorphisms of systems of equations JO - Archivum mathematicum PY - 1977 SP - 135 EP - 140 VL - 13 IS - 3 UR - http://geodesic.mathdoc.fr/item/ARM_1977_13_3_a1/ LA - en ID - ARM_1977_13_3_a1 ER -