1. 1) Bonet, J.: Boeing ERA N+2 Advanced Vehicle Concept Results, 50th AIAA Aerospace Sciences Meeting, 2012.
2. 2) Drake, A.: NASA Environmentally Responsible Aviation (ERA) N+2 Advanced Vehicle Study, 50th AIAA Aerospace Sciences Meeting, 2012.
3. 3) Lockheed Martine ERA Team: NASA Environmentally Responsible Aviation, 50th AIAA Aerospace Sciences Meeting, 2012.
4. 4) Mangelsdorf, M.: Environmentally Responsible Aviation N+2 Advanced Vehicle Concepts NRA Status, Turbo Expo, 2011.
5. 5) Airbus: The A320 New Engine Option, http://www.airbus.com/aircraftfamilies/passengeraircraft/a320family/spotlight-on-a320neo/ (accessed May 31, 2013).