IEC 60027 Letter Symbols to be used in electrical technology (Edition 4.0)
IEC 61082-1:2014 Preparation of Documents used in electrotechnology - Part 1: Rules
IEC 61286:2001 Information technology - Coded graphic character set for use in the preparation of documents used in electrotechnology and for information interchange
IEC 81714-2:2006 Design of graphical symbols for use in the technical documentation of products - Part 2: Specification for graphical symbols in a computer sensible form, including graphical symbols for a reference library, and requirements for their interchange
ISO 31 Quantities and units — Part 9: Atomic and nuclear physics — Amendment 1
ISO 81714-1:2010 Design of graphical symbols for use in the technical documentation of products - Part 1: Basic rules
ISO/IEC 10646:2014 Information technology - Universal Coded Character Set (UCS)