Von Braun was awarded a doctorate in physics (aerospace engineering) on 27 July 1934, from the University of Berlin for a thesis entitled ""About Combustion Tests""; his doctoral supervisor was Erich Schumann. However, this thesis was only the public part of von Braun's work. His actual full thesis, "Construction, Theoretical, and Experimental Solution to the Problem of the Liquid Propellant Rocket" (dated 16 April 1934) was kept classified by the German army, and was not published until 1960. By the end of 1934, his group had successfully launched two liquid fuel rockets that rose to heights of 2.2 and .