ETSI EN 300 369-6 Final draft Version 1.5.1Integrated Services Digital Network (ISDN); Explicit Call Transfer (ECT) 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

standard by European Telecommunications Standards Institute, 01/01/2002