Real-time voice over packet-switched networks. - T. J. Kostas; Michael S. Borella; Ikhlaq Sidhu; Guido M. Schuster; Jacek Grabiec; Jerry Mahler (IEEE Netw., 1998)

True number portability and advanced call screening in a SIP-based IP telephony system. - Ismail Dalgic; Michael S. Borella; Rick Dean; Jacek Grabiec; Jerry Mahler; Guido M. Schuster; Ikhlaq Sidhu (IEEE Commun. Mag., 1999)