Integrated Services Digital Network (ISDN) - Signalling System No.7 (SS7) - ISDN User Part (ISUP) version 4 for the international interface - Part 19: Three-Party (3PTY) supplementary service [ITU-T Recommendation Q.734, clause 2 (1996) and implementors guide (1998), modified]
Edition 2001-11-01

Integrated Services Digital Network (ISDN) - Digital Subscriber Signalling System No. one (DSS1) protocol - Three-Party (3PTY) supplementary service - Part 6: Abstract Test Suite (ATS) and partial Protocol Implementation eXtra Information for Testing (PIXIT) proforma specification for the network (incl. Diskette!!!)
Edition 2002-07-01

Integrated Services Digital Network (ISDN) - Digital Subscriber Signalling System No. one (DSS1) protocol - Three-Party (3PTY) supplementary service - Part 4: Abstract Test Suite (ATS) and partial Protocol Implementation eXtra Information for Testing (PIXIT) proforma specification for the user (incl. Diskette!!!)
Edition 2002-07-01

Integrated Services Digital Network (ISDN) - Three Party (3PTY) supplementary service - Digital Subscriber Signalling System No. one (DSS1) protocol - Part 1: Protocol specification
Edition 1998-09-01

Integrated Services Digital Network (ISDN) - Three Party (3PTY) supplementary service - Digital Subscriber Signalling System No. one (DSS1) protocol - Part 2: Protocol Implementation Conformance Statement (PICS) proforma specification (incl. Diskette!!!)
Edition 1998-10-01

Integrated Services Digital Network (ISDN) - Three Party (3PTY) 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 1998-09-01

Integrated Services Digital Network (ISDN) - Three Party (3PTY) 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 1998-09-01

Information Technology - Security Techniques - Guidelines for the Use and Management of Trusted Third Party Services
Edition 2004-01-01

Information and documentation. Trusted third party repository for digital records
Edition 2017-11-03

Intelligent transport systems - eCall - Operating requirements for third party support
Edition 2013-02-13