1. Apparatus with one or more particular functions for connection to public switched telephone networks run by certain public telecommunications operators. Specification for apparatus with call barring facilities Part 7, (30th November 1988) Authors: British Standards Institution, Record Type: Book Extent: 1 online resource (12 pages) View Content: Available online (eLD content is only available in our Reading Rooms) ↗
2. Private branch exchanges for connection to public switched telephone networks run by certain public telecommunication operators. Simple call-routing mode (SCRM). Specification for the simple call-routing mode of PBX operation, with terminating stations treated as an entirety Part 6-6.1, (30th September 1988) Authors: British Standards Institution, Record Type: Book Extent: 1 online resource (21 pages) View Content: Available online (eLD content is only available in our Reading Rooms) ↗
3. Private branch exchanges for connection to public switched telephone networks run by certain public telecommunication operators. Specification for general requirements Part 1, (1st September 1988) Authors: British Standards Institution, Record Type: Book Extent: 1 online resource (27 pages) View Content: Available online (eLD content is only available in our Reading Rooms) ↗
4. Private branch exchanges for connection to public switched telephone networks run by certain public telecommunication operators.Facilities on private branch exchanges. Specification for facilities on private branch exchanges with terminating stations treated as an entirety Part 5-5.1, (30th September 1988) Authors: British Standards Institution, Record Type: Book Extent: 1 online resource (40 pages) View Content: Available online (eLD content is only available in our Reading Rooms) ↗