Virtual Roaming Systems for GSM, GPRS and UMTS: Open Connectivity in PracticeE-bookVirtual Roaming Systems for GSM, GPRS and UMTS: Open Connectivity in PracticediArnaud Henry-LabordereValutazione: 5 su 5 stelle5/5Salva Virtual Roaming Systems for GSM, GPRS and UMTS: Open Connectivity in Practice per dopo