Data communication networks: services and facilities interfaces VIII.3 X.40-X.181 Data communication networks: transmission signalling and switching network aspects maintenance and administrative arrangements VIII.4 X.200-X.219 Data communication networks. Open Systems Interconnection (OSI - model and notation service definition VIII.5 X.220-X.290 Data communication networks: Open Systems Interconnection (OSI) - protocol specifications conformance testing VIII.6 X.300-X.370 Data communication networks: interworking between networks mobile data transmission systems VIII.7 X.400-X.420 Data communication networks: message handling systems VIII.8 X.500-X.521 Data communication networks: directory Protection against interference Construction installation and protection of cable and other elements of outside plant Z.100 and Functional Specification and Description Language (SDL) Annexes A;B;C;E Criteria for using Formal Description Techniques (FDTs) Z.110 Z.100, Annex D SDL user guidelines Z.100, Annex F.1 SDL formal definition Introduction Z.100, Annex F.2 SDL formal definition. Static semantics Z.100, Annex F.3 SDL formal definition. Dynamic semantics Z.200 CCITT High Level Language (CHILL) Z.301-Z.341 Man-machine Language (MML) Terms, definitions, abbreviations, acronyms, series and recommendations Index of Blue Book 22/12 Telecommunication standards 2. For standards of radio systems world-wide, relating to com- patible performance and interconnectivity. Table 22.5 CCIR/CCITT Joint Study Groups 3. For the production of information used for the development, planning and operation of radio systems, with special emphasis Study Group Activity on the needs of developing countries. Television and sound transmission Co-ordination committee for vocabulary 22.3.3.2 CCIR organisation and output The CCIR membership is similar to that of the CCITT and it operates on similar principles. CCIR Recommendations are pub- lished by Plenary Assemblies which meet every four years. The Table 22.6 CCIR 1990 Recommendations CCIR is not as 