Shaojing Fan Jianbo Fan Yongping Zhang Zhongkun He An Optimized Scheme for Mobile Learning on IP-Based Network Using SIP. 541-551 2008 ICWL https://doi.org/10.1007/978-3-540-85033-5_53 conf/icwl/2008 db/conf/icwl/icwl2008.html#FanFZH08