DIN EN 301702:2003-08
Digital cellular telecommunications system (Phase 2+) (GSM) - User-to-User Signalling (UUS) - Service description, Stage 1 (GSM 02.87 version 7.1.2 Release 1998) (Endorsement of the English version EN 301702 V 7.1.2 (1999-12) as German standard) / Note...