2Air Force Civil Engineer Support Agency (Preparing Activity,), U.S. Army Corps of Engineers, Naval Facilities Engineering Command. Unified Facilities Criteria (UFC). UFC 3 - 260 - 01. Airfield and heliport planning and design [ S ]. 1 November 2001, Change of 19 May 2006. A18:1-9.
3Australian Government Civil Aviation Safety Authority. AC 172 - 03 (0). Control tower principles[ S ]. May 2007 : 1-4.
4Unified Facilities Criteria (UFC). UFC 4 - 133 -01N. Navy air waffle control facilities[ S]. 24 February 2005. Including changes 1 and2, 7 March 2007:1-61.