On the German Art of War: Truppenführung (Art of War)

English translation of the military manual that guided the German Army in World War II This book was carried into battle by officers and NCOs and had been classified by the U.S. Army until the year 2000 Topics include command, attack, defense, tanks, chemical warfare, logistics, and more
Truppenführung ("unit command") served as the basic manual for the German Army from 1934 until the end of World War II and laid the doctrinal groundwork for blitzkrieg and the early victories of Hitler's armies. Reading it is as close to getting inside the minds behind the Third Reich's war machine as you are likely to get.