Integrated Services Digital Network (ISDN); Multiple Subscriber Number (MSN) supplementary service - Digital Subscriber Signalling System No. one (DSS1) protocol - Part 2: Protocol Implementation Conformance Statement (PICS) proforma specification (Endorsement of the English version EN 300052-2 V 1.2.4 (1998-06) as German standard)
综合业务数字网(ISDN);多用户号码(MSN)补充业务.数字用户信号发送系统第1号(DSS1)协议.第2部分:协议实施一致性声明(PICS)形式规范(英文版EN 300052-2 V 1的认可)