DIN EN 300185-1:2000
综合业务数字网(ISDN).会议呼叫加入(CONF)补充业务.数字用户用1号信令系统(DSS1)协议.第1部分:协议规范
Integrated Services Digital Network (ISDN) - Conference call, add-on (CONF) supplementary service - Digital Subscriber Signalling System No. one (DSS 1) protocol - Part 1: Protocol specification (Endorsement of the English version EN 300185-1 V 1.2.4 (199