ETSI TS 124 206-2007 数字蜂窝通信系统(第2+阶段).全球移动通信系统(UMTS).电路交换(CS)和IP多媒体子系统(IMS)间的语音呼叫连续性.第3阶段(版本7.2.0).3GPP TS 24.206(版本7.2.0,第7次发布)
Digital cellular telecommunications system (Phase 2+); Universal Mobile Telecommunications System (UMTS); Voice call continuity between Circuit Switched (CS) and IP Multimedia Subsystem (IMS); Stage 3 V7.2.0; 3GPP TS 24.206 version 7.2.0 Release 7