By Keil, Charles
By Frants, Valery I., Shapiro, Jacob, Voiskunskii, Vladimir G.
By Abrate, Serge
By Piggott, Derek
By W. McCormick, Barnes
By David Baker
By Edgerton, David
By Department of the Army, Headquarters
By Rogers, Lucy
By Beer, Ferdinand P., Johnston Jr., E. Russell, Mazurek, David
By Mike Burton
By Moolman, Valerie
By Bickers, Richard Townshend
By Farkas, Bart
By Tony Blackman
By G. J. Christopher Paul
By Dr Gareth Moore
By David J. Smith
By Heinz J. Nowarra
By Anthony Lawrence
By S. Newman (Lecturer in Helicopter Engineering, Department of Aeronautics & Astronautics, Southampton University)
By Dilip Sarkar
By PAUL BRICKHILL.
By Mary S. Lovell