DIN ETS 300356-19:1995-11
Отменен
Integrated Services Digital Network (ISDN) - Signalling System No. 7 - ISDN User Part (ISUP) version 2 for the international interface - Part 19: Three-Party (3PTY) supplementary service [ITU-T Recommendation Q.734, clause 2 (1993), modified]; English version ETS 300356-19:1995
