IEC 60635 Amd.1 Ed. 1.0 b:1997
Amendment 1 - Toroidal strip-wound cores made of magnetically soft material
Amendment by International Electrotechnical Commission, 10/09/1997
IEC 60524 Amd.2 Ed. 1.0 b:1997
Amendment 2 - Direct-current resistive volt ratio boxes
Amendment by International Electrotechnical Commission, 10/09/1997
IEC 61229 Amd.1 Ed. 1.0 b:1998
Amendment 1 - Rigid protective covers for live working on a.c. installations
Amendment by International Electrotechnical Commission, 02/26/1998