Integrated Services Digital Network (ISDN) - Signalling System No. 7 (SS7); ISDN User Part (ISUP) V 4 interactions with the Intelligent Network Application Part (INAP) - Part 1: Protocol specification (ITU-T-Recommendation Q.1601:1999, modified) (Endorsement of the English version EN 301464 V 1.1.1 (2000-12) as German Standard)