Terrestrial Trunked Radio (TETRA) - Voice plus Data (V+D) - Part 12: Supplementary services stage 3; Sub-part 12-24: Call Retention (CRT) (Endorsement of the English version ETS 300392-12-24:2000-09 as German Standard)
Edition 2001-08

Terrestrial Trunked Radio (TETRA) - Voice plus Data (V+D) - Part 11: Supplementary services stage 2; Sub-part 21: Ambience Listening (AL) (Endorsement of the English version EN 300392-11-21 V 1.1.1 (2003-04) as German standard)
Edition 2003-11

Terrestrial Trunked Radio (TETRA) - Voice plus Data (V+D) - Part 11: Supplementary services stage 2; Sub-part 4: Call Forwarding (CF) (Endorsement of the English version EN 300392-11-4 V 1.1.1 (2003-07) as German standard)
Edition 2003-11

Terrestrial Trunked Radio (TETRA) - Voice plus Data (V+D) - Part 12: Supplementary services stage 3; Sub-part 17: Include Call (IC) (Endorsement of the English version EN 300392-12-17 V 1.1.2 (2002-01) as German standard)
Edition 2003-04

Terrestrial Trunked Radio (TETRA) - Voice plus Data (V+D) - Part 12: Supplementary services stage 3; Sub-part 18: Barring of Outgoing Calls (BOC) (Endorsement of the English version EN 300392-12-18 V 1.1.1 (2001-08) as German standard)
Edition 2003-04

Terrestrial Trunked Radio (TETRA) - Voice plus Data (V+D) - Part 12: Supplementary services stage 3; Sub-part 19: Barring of Incoming Calls (BIC) (Endorsement of the English version EN 300392-12-19 V 1.1.1 (2001-08) as German standard)
Edition 2003-04

Terrestrial Trunked Radio (TETRA) - Voice plus Data (V+D) - Part 11: Supplementary services stage 2; Sub-part 17: Include Call (IC) (Endorsement of the English version EN 300392-11-17 V 1.1.2 (2002-01) as German standard)
Edition 2003-04

Terrestrial Trunked Radio (TETRA) - Voice plus Data (V+D) - Part 11: Supplementary services stage 2; Sub-part 18: Barring of Outgoing Calls (BOC) (Endorsement of the English version EN 300392-11-18 V 1.1.1 (2001-08) as German standard)
Edition 2003-04

Terrestrial Trunked Radio (TETRA) - Voice plus Data (V+D) - Part 11: Supplementary services stage 2; Sub-part 19: Barring of Incoming Calls (BIC) (Endorsement of the English version EN 300392-11-19 V 1.1.1 (2001-08) as German standard)
Edition 2003-04

Terrestrial Trunked Radio (TETRA) - Voice plus Data (V+D) - Part 11: Supplementary services stage 2; Sub-part 14: Late Entry (LE) (Endorsement of the English version EN 300392-11-14 V 1.1.1 (2002-07) as German standard)
Edition 2003-04