Weizsacker, 'Memoirs'. Reference should also be made to Hitler's many remarks at that time in which he emphasizes his determination to take risks and indeed turns this determination into the very criterion for statesmanship. See his speech to the commanders of the Wehrmacht of 22nd August 1939, quoted by Freund, Geschichte des Zweiten Weltkrieges, Vol. III; also Franz Halder, 'Kriegstagebuch', Vol. I