DIN ETS 300529:2001 数字移动电话远程通信系统(阶段2).补充服务技术的实现 (英文版本核准本 ETS 300529:1996-11 作为德国标准)
Digital cellular telecommunications system (Phase 2) - Technical realisation of supplementary services (Endorsement of the English version ETS 300529:1996-11 as German standard)