ETSI TS 101 504

Digital cellular telecommunications system (Phase 2 ) (GSM); Inband Tandem Free Operation (TFO) of Speech Codecs; Service Description; Stage 3 (GSM 08.62 version 8.0.1 Release 1999) Edition: 8.0.1
European Telecommunications Standards Institute / 01-Aug-2000 / 70 pages