ETSI PRTBR 038-1997 公共交换电话网(PSTN).对终端设备并入在将其连入欧洲PSTN的模拟接口时能够支持其正常业务的模拟手机功能的附加要求
Public Switched Telephone Network (PSTN); Attachment Requirements for a Terminal Equipment Incorporating an Analogue Handset Function Capable of Supporting the Justified Case Service when Connected to the Analogue Interface of the PSTN in Europe