4 Dau, K., Characteristics of a rectangular wing with a peripheral jet in ground effect: Part I/' Institute of Aerophysics, Univ. of Toronto, Toronto, Ontario, Canada, Note 56 (September 1961). 5 Webb, W. B., Annular jet stability analyses in hovering, Bell Helicopter Co. Rept. 8034-099-001 (September 1960). 6 Liiva, J., Gyrostabilisation of an elliptic wing with peripheral jet hovering in ground effect/' Institute of Aerophysics, Univ. of Toronto, Toronto, Ontairo, Canada, Note 60 (August 1962). 7 Webster, W. C., The static stability of ground effect machines—thin jet theory, Hydronautics Co., Rockville, Md., Rept. 011-1 (December 1960). 8 Lin, J. D., The static stability of ground effect machines— thick jet theory, Hydronautics Co., Rockville, Md., Rept. 011-2 (June 1961). 9 Scott, W. J., Asymmetry of annular jet flow in ground proximity, Institute of Aerophysics, Univ. of Toronto, Toronto, Ontairo, Canada, Note 61 (May 1962). 10 Magnus, R. J., Use of vortices in the calculation of bottom pressures of annular jet ground effect machines, Convair Report (March 1961). 11 Yen, B., Patterns of flow under a two-dimensional GEM, Iowa Institute of Hydronautics, Research Report (January 1962). 12 Chaplin, H. R., Ground effect machine research and development in the United States, David Taylor Model Basin Rept. 944 (December 1960). 13 Poisson-Quiiiton, P. and Bevert, A., The principle and applications of ground effect vehicles, Bull. Assoc. Tech. Maritime Aeronaut. 60, 61-89 (1960).