ETSI TS 100 602 Digital cellular telecommunications system (Phase 2+) (GSM); Interworking between the Public Land Mobile Network (PLMN) and the Packet Switched Public Data Network (PSPDN) for Packet Assembly/Disassembly (PAD) facility access (GSM 09.05 version 6.0.0 Release 1997)

standard by European Telecommunications Standards Institute, 04/01/1999