Private Telecommunication Network (PTN); signalling at the S-reference point; generic keypad protocol for the support of supplementary services; English version ETS 300190:1992
Edition 1993-09

Private Telecommunication Network (PTN); signalling protocol at the S-reference point; identification supplementary services; English version ETS 300191:1992
Edition 1993-09

Private Telecommunication Network (PTN); signalling protocol at the S-reference point; circuit mode basic services; English version ETS 300192:1992
Edition 1993-09

Integrated Services Digital Network (ISDN) - Audiovisual services - Frame structure for a 64 kbit/s to 1920 kbit/s channel and associated syntax for inband signalling; English version ETS 300144:1996
Edition 1996-08