ETSI TS 122 129
ETSI TS 122 129
Digital cellular telecommunications system (Phase 2+) (GSM); Universal Mobile Telecommunications System (UMTS); Handover Requirements between UMTS and GSM or other Radio Systems (3G TS 22.129 version 3.2.0 Release 1999)
standard published 01/01/2000 by European Telecommunications Standards Institute