ETSI PRETS 300 369-1-1996 综合业务数字网(ISDN).显式呼叫转移(ECT)补充业务.数字用户1号信令系统(DSS1)协议.第1部分:协议规范(第2版)
Integrated Services Digital Network (ISDN); Explicit Call Transfer (ECT) Supplementary Service; Digital Subscriber Signalling System No. One (DSS1) Protocol; Part 1: Protocol Specification Second Edition