"Kite Power". Optimisation in Engineering Center (OPTEC) Katholieke Universiteit Leuven. 2010-01-19. Archived from the original on 2011-05-20. Retrieved 2010-01-19.
"Kite Power". Optimisation in Engineering Center (OPTEC) Katholieke Universiteit Leuven. 2010-01-19. Archived from the original on 2011-05-20. Retrieved 2010-01-19.