DIN ETS 300356-16:1995-11
Отменен
Integrated Services Digital Network (ISDN) - Signalling System No. 7 - ISDN User Part (ISUP) version 2 for the international interface - Part 16: Call Hold (HOLD) supplementary service [ITU-T Recommendation Q.733, clause 2 (1993), modified]; English version ETS 300356-16:1995
