ITU-T Rec. D.232 (1991) – SPECIFIC TARIFF AND ACCOUNTING PRINCIPLES APPLICABLE TO ISDN SUPPLEMENTARY SERVICES
FOREWORD
1 Introduction
2 Charging aspects
    2.1 Number identification
        2.1.1 Charging principles
    2.2 Direct dialling-in and multiple subscriber number
        2.2.1 Charging principles
    2.3 Call forward and call transfer
        2.3.1 Charging principles
    2.4 Line Hunting
        2.4.1 Charging principles
    2.5 Call Waiting and Call Hold
        2.5.1 Charging principles
    2.6 Conference calls
        2.6.1 Charging principles
    2.7 Closed User Group
        2.7.1 Charging principles
    2.8 Advice of Charge
        2.8.1 Charging principles
3 Accounting
4 Charging mechanisms and support requirements
ANNEX A – Summary of charging mechanisms and support requirements for supplementary services