3ATA. Standard Method of Estimating Comparative Direct Operating Costs of Turbine Powered Transport Airplanes [ R ]. Washington DC, 1967.
4Liebeck R. H. Advanced Subsonic Airplane design and E- conomic Studies. NASA CR- 195443, April 1995. Curran, R. , Value-Driven Design and Operational Value, in Encyclopedia of Aerospace Engineering. 2010, John Wiley & Sons.