1. Service requirements for the Internet Protocol (IP) Multimedia core network Subsystem (IMS)
2. IP Multimedia Core Network Subsystem (IMS) Multimedia Telephony Service and supplementary services; Stage 1
3. GSMA IMS Profile for Voice and SMS 2013
4. GSMA IMS Profile for Conversational Video Service 2013
5. Looking at LTE in Practice: A Performance Analysis of the LTE System based on Field Test Results;Elnashar;IEEE Vehicular Technology Magazine,2013