1. European Aeronautics: A vision 2020. Report of the Group of personalities, ACARE, Brussels, Office of Official Publications of the European Communities, Luxemburg, 2001, pp. 26. (also see: 〈〈http://www.acare4europe.com/docs/Vision2020_0.pdf〉〉 (05/03/2013)).
2. Europe's Vision for Aviation. Report of the High Level Group on Aviation Research;Flightpath 2050,2011
3. Strategic Research and Innovation Agenda (SRIA) vol.1., ACARE (Advisory Council for Aviation Research and Innovation in Europe), 2011, pp. 152 〈www.acare4europe.org〉.
4. National Aeronautics and Space Administration. “NASA Aeronautics Blueprint: Towards a Bold New Era in Aviation.” Washington, D.C., 2002.
5. Truman, T., A. de Graaff. Out of the box, Ideas about the future of air transport, Part 1, ASTERA/ ACARE, Koninklijke de Swart, Den Haag, 2006, p. 108. Part 2, EC Directorate-General for Research, ACARE, Brussels, 2007. p. 91.