Telecommunication-time metering device utilizable for prepayment
Telephone calling card service system integrating virtual...
Telephone calling card system with abbreviated code...
Telephone calling card with enhanced features
Telephone card having calendar function and system for using sam
Telephone set
Telephone set
Telephone system
Telephony platform and method for providing enhanced...
Telephony system for calling card calls
Transmitter for accessing pay-type telephones
Transportable logic to facilitate a large calling card...