YDN 030.2-1997
通用个人通信(UPT)、广域集中用户交换机(WAC)、电话投票(VOT)和大众呼叫(MAS)的编号和拔号程序(内部标准)
Code number and dialing procedure of universal personal telecommunication, wide area Centrex switch (WAC), vote of telephone (VOT) and mass calling (MAS) services (internal standard)