US 6314362 Method and system for an automated tool for en route traffic controllers
rtca.org
Final report of the RTCA Task Force 3, Free Flight Implementation. RTCA, Inc., Washington, DC, Oct 26, 1995 [1]Archived 2008-04-08 at the Wayback Machine
web.archive.org
Final report of the RTCA Task Force 3, Free Flight Implementation. RTCA, Inc., Washington, DC, Oct 26, 1995 [1]Archived 2008-04-08 at the Wayback Machine