Tham khảo Tàu lượn

  1. ↑ Harwood, Craig S. and Fogel, Gary B. Quest for Flight: John J. Montgomery and the Dawn of Aviation in the West, University of Oklahoma Press 2012.
  2. ↑ The Fédération Aéronautique Internationale Hang Gliding Diploma (2006) for the invention of the modern hang glider: FAI Award: The FAI Hang Gliding Diploma
  3. ↑ FAI Sporting Code Section 7