Toward the PSTN/Internet Inter-Networking-Pre-PINT Implementations. - Hui-Lan Lu; Murali Krishnaswamy; Lawrence Conroy; Steven M. Bellovin; Fred M. Burg; Antonio DeSimone; Kamlesh T. Tewani; Paul Davidson; Henning Schulzrinne; Kumar Vishwanathan (RFC, 1998)