(WITHDRAWN) Stage 2 and Stage 3 Description for the Q3 Interface - Alarm Surveillance - Specifications of Signalling System No. 7 Q3 Interface (Study Group XI) 50 pp
(WITHDRAWN) Stage 2 and Stage 3 Description for the Q3 Interface - Alarm Surveillance - Specifications of Signalling System No. 7 Q3 Interface (Study Group XI) 50 pp