1. Action plan 16: Common trajectory prediction capability. https://acy.tc.faa.gov/cpat/tjm/TP_Requirements_Engineering_Methodology.pdf. Action plan 16: Common trajectory prediction capability. https://acy.tc.faa.gov/cpat/tjm/TP_Requirements_Engineering_Methodology.pdf.
2. Aircraft operating expenses. http://www.opshots.net/2015/04/aircraft-operating-series-aircraft-operating-expenses/. Aircraft operating expenses. http://www.opshots.net/2015/04/aircraft-operating-series-aircraft-operating-expenses/.
3. Aircraft situation display to industry. http://www.fly.faa.gov/ASDI/asdi.html. Aircraft situation display to industry. http://www.fly.faa.gov/ASDI/asdi.html.
4. Definition of an aircraft trajectory by icao. http://ap16.atmrt.org/. Definition of an aircraft trajectory by icao. http://ap16.atmrt.org/.
5. Google earth. https://www.google.com/earth//. Google earth. https://www.google.com/earth//.