PRETS 300 179-1991 综合业务数字网(ISDN); Advice of Charge: Charging Information During the Call(AOC-D)补充服务服务说明(T/NA1(89)14)
Integrated Services Digital Network (ISDN); Advice of Charge: Charging Information During the Call (AOC-D) Supplementary Service Service Description (T/NA1(89)14)