Recommendation U.12 (11/1988): Terminal and transit control signalling system for telex and similar services on international circuits (type D signalling)
superseded recommendation/international standard from the International Telecommunication Union
ITU Telecommunication Standardization Sector
Terminal and transit control signalling system for telex and similar services on international circuits (type D signalling)
Recommendation F.69 (11/1988): Plan for telex destination codes
Recommendation S.9 (11/1988): Switching equipment of start-stop apparatus
Recommendation U.1 (11/1988): Signalling conditions to be applied in the international telex service
Recommendation U.11 (11/1988): Telex and gentex signalling on intercontinental circuits used for intercontinental automatic transit traffic (type C signalling)
Recommendation U.15 (11/1988): Interworking rules for international signalling systems according to Recommendations U.1, U.11 and U.12