Mischa Schmidt Bernd Lamparter Stefan Schmid Voice Call Continuity - A Critical Step Towards All-IP Based Next Generation Networks. 5579-5583 2008 GLOBECOM http://dx.doi.org/10.1109/GLOCOM.2008.ECP.1066 conf/globecom/2008 db/conf/globecom/globecom2008.html#SchmidtLS08