1. Bauknecht, A., Merz, C.B., Landolt, A., Meier, A.H., Raffel, M.: Blade tip vortex detection in maneuvering flight using the background oriented schlieren (bos) technique. In: Proceedings of the American Helicopter Society, 69th Annual Forum (2013)
2. Bhattacharyya, S., Conlisk, A.: The structure of the rotor wake in ground effect. In: AIAA 41th Aerospace Sciences Meeting and Exhibit (2003)
3. Brown, R.E., Whitehouse, G.R.: Modelling rotor wakes in ground effect. J. Am. Helicopter Soc. 49(3), 238–249 (2004)
4. Cheeseman, I.C., Bennett, W.E.: The effect of the ground on a helicopter rotor in forward flight. A.A.E.E. Report Rey./288 3021, Aeronautical Research Council (1955)
5. Curtiss, H.C., Sun, M., Putman, W.F., Hanker Jr., W.J.: Rotor aerodynamics in ground effect at low advance ratios. In: Proceedings of the American Helicopter Society, 37th Annual Forum (1981)