TY - JOUR T1 - O definícii A1 - Bálint, Vojtech JA - Obzory matematiky, fyziky a informatiky Y1 - 2015 VL - 44 IS - 2 SP - 9 EP - 12 SN - 1335-4981 N2 - The paper explains why it is appropriate from the didactic point of view for the study include the definition in the shape of the equivalence. ER -