Standards
[CURRENT]
NF Z82-139
; NF ETS 300139:1994-09-01
NF Z82-139
; NF ETS 300139:1994-09-01
Integrated Services Digital Network (ISDN). Call hold (hold) supplementary service. Service description
Title (German)
INTEGRATED SERVICES DIGITAL NETWORK (ISDN). DIENSTMERKMAL HALTEN. DIENSTBESCHREIBUNG