The pathophysiology of high sustained +Gz acceleration, limitation to air combat manoeuvering and the use of centrifuges in performance training : papers presented at the Aerospace medical panel specialists' meeting held in Copenhagen, Denmark, 5-9 April 1976 / edited by Neville P. Clarke,... and Sidney D. Leverett,... ; North Atlantic treaty organization, Advisory group for aerospace research and development (Organisation du traité de l'Atlantique nord)