2011IEC 60601-2-25:2011 Medical electrical equipment - Part 2-25: Particular requirements for basic safety and essential performance of electrocardiographs
1970IEC 60601-2-25:1993/AMD1:1999 Amendment 1 - Medical electrical equipment - Part 2-25: Particular requirements for the safety of electrocardiographs
1993IEC 60601-2-25:1993 Medical electrical equipment; part 2: particular requirements for the safety of electrocardiographs