Recommendation ITU-T Z.111 provides meta-grammars for ITU-T Recommendations that define ITU-T languages in the X.680 series and the Z series of ITU-T Recommendationson languages for specification, implementation, modelling and testing. This allows the description of these meta-grammars that define the abstract or concrete grammar (syntax, constraints and semantics) of languages without having to repeat the meta-grammar (such as lexical naming rules, or the description of Backus-Naur Form syntax) as a preamble or annex to each language definition.
ITU-T Z.111-2008 Referenced Document
ITU-T T.55-2008 Use of the universal multiple-octet coded character set (UCS) (Study Group 16)
ITU-T Z.111-2008 history
2008ITU-T Z.111-2008 Notations and guidelines for the definition of ITU-T languages Study Group 17