1. B. Brewin, Nation's networks see sharp volume spikes after attacks, Computerworld, September 17, 2001.
2. Computer Science and Telecommunications Board, The Internet Under Crisis Conditions: Learning from September 11. 2002.
3. Internet Engineering Task Force, Internet Emergency Preparedness Working Group, http://www.ietf.org/html.charters/ieprep-charter.html.
4. Standards initiatives for emergency telecommunications service (ETS);Folts;IEEE Communications Magazine,2002
5. Framework for supporting ETS in IP telephony;Carlberg;Work-in-Progress, Internet Engineering Task Force, Internet Draft,2004