UNE-ETS 300954 Ed1:2005 Digital cellular telecommunications system; Multi Party (MPTY) supplementary services; Stage 3 (GSM 04.84 version 5.0.1) (Endorsed by AENOR in November of 2005.)
2005UNE-ETS 300954 Ed1:2005 Digital cellular telecommunications system; Multi Party (MPTY) supplementary services; Stage 3 (GSM 04.84 version 5.0.1) (Endorsed by AENOR in November of 2005.)