Integrated Services Digital Network (ISDN) - Digital Subscriber Signalling System No. one (DSS1) protocol; teleaction service - Part 3: Test Suite Structure and Test Purposes (TSS&TP) specification for the End User Terminal (EUT) (Endorsement of the English version EN 301145-3 V 1.1.6 (1999-11) as German Standard)
Edition 2000-10

Integrated Services Digital Network (ISDN) - Digital Subscriber Signalling System No. one (DSS1) protocol; teleaction service - Part 5: Test Suite Structure and Test Purposes (TSS&TP) specification for the Service Provider Terminal (SPT) (Endorsement of the English version EN 301145-5 V 1.1.6 (1999-11) as German Standard)
Edition 2000-10

Integrated Services Digital Network (ISDN) - Teleaction teleservice - Service description
Edition 2001-12-01

Integrated Services Digital Network (ISDN) - Digital Subscriber Signalling System No. one (DSS1) protocol - Data link layer - Part 1: General aspects [ITU-T Q.920 (1993), modified]; English version ETS 300402-1:1995
Edition 1996-06

Integrated Services Digital Network (ISDN) - Digital Subscriber Signalling System No. one (DSS1) protocol - Data link layer - Part 2: General protocol specification [ITU-T Q.921 (1993), modified]; English version ETS 300402-2:1995
Edition 1996-06