Guderian's leadership was supported, fostered and institutionalised by his supporters in the Reichswehr General Staff system, which worked the Army to greater and greater levels of capability through massive and systematic Movement Warfare war games in the 1930s. Guderian's book incorporated the work of theorists such as , whose book, "The Tank War" ("Der Kampfwagenkrieg") (1934) gained a wide audience in the German army. Another German theorist, Ernst Volckheim, wrote a huge amount on tank and combined arms tactics and was influential to German thinking on the use of armoured formations but his work was not acknowledged in Guderian's writings.