Integrated Services Digital Network (ISDN) - Completion of Calls to Busy Subscriber (CCBS) supplementary service - Digital Subscriber Signalling System No. one (DSS1) protocol - Part 3: Test Suite Structure and Test Purposes (TSS&TP) specification for the user
Edition 2001-09-01

Integrated Services Digital Network (ISDN) - Completion of Calls to Busy Subscriber (CCBS) supplementary service - Digital Subscriber Signalling System No. one (DSS1) protocol - Part 4: Abstract Test Suite (ATS) and partial Protocol Implementation eXtra Information for Testing (PIXIT) proforma specification for the user (incl. Diskette!!!)
Edition 2002-02-01

Integrated Services Digital Network (ISDN) - Completion of Calls to Busy Subscriber (CCBS) supplementary service - Digital Subscriber Signalling System No. one (DSS1) protocol - Part 5: Test Suite Structure and Test Purposes (TSS&TP) specification for the network
Edition 2001-09-01

Integrated Services Digital Network (ISDN) - Completion of Calls to Busy Subscriber (CCBS) supplementary service - Digital Subscriber Signalling System No. one (DSS1) protocol - Part 6: Abstract Test Suite (ATS) and partial Protocol Implementation eXtra Information for Testing (PIXIT) proforma specification for the network (incl. Diskette!!!)
Edition 2002-02-01

Private Integrated Services Network (PISN) - Specification, functional model and information flows - Call offer supplementary service [ISO/IEC 14841 (1996) modified]
Edition 2003-09-01

Private Integrated Services Network (PISN) - Inter-exchange signalling protocol - Call offer supplementary service [ISO/IEC 14843 (2003), modified]
Edition 2004-03-01

Private Integrated Services Network (PISN) - Specification, functional model and information flows - Do not disturb and do not disturb override supplementary services [ISO/IEC 14842 (1996) modified]
Edition 2003-09-01

Private Integrated Services Network (PISN) - Inter-exchange signalling protocol - Do not disturb and do not disturb override supplementary services [ISO/IEC 14844 (2003), modified]
Edition 2004-03-01

Private Integrated Services Network (PISN) - Specification, functional model and information flows - Call completion supplementary services [ISO/IEC 13866 (1995) modified]
Edition 2003-09-01

Private Integrated Services Network (PISN) - Inter-exchange signalling protocol - Call completion supplementary services [ISO/IEC 13870 (2003), modified]
Edition 2004-03-01