ÖNORM EN 300356-1 V 4.2.1:2001-11
Действует
Integrated Services Digital Network (ISDN) - Signalling System No.7 (SS7) - ISDN User Part (ISUP) version 4 for the international interface - Part 1: Basic services [ITU-T Recommendations Q.761 to Q.764 (1999), modified]
