Moonkoo Kim Jonghyun Park Jonghyun Paik Factors Influencing Adoption for Activating Mobile VoIP. 470-472 2009 APNOMS http://dx.doi.org/10.1007/978-3-642-04492-2_55 conf/apnoms/2009 db/conf/apnoms/apnoms2009.html#KimPP09