ÖNORM EN 300141-4 V 1.3.3:2000-09
Действует
Integrated Services Digital Network (ISDN) - Call Hold (HOLD) 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!!!)
