Konrad Heiden, "Adolf Hitler. Das Zeitalter der Verantwortungslosigkeit", Vol. I. For this period Heiden depends extensively on the remarks of Reinhold Hanisch, which also need to be read with caution. However, Hitler's depraved and dishevelled appearance is reported elsewhere in Heiden and also in Jetzinger, Hitler's Youth. In other respects Heiden's portrayal is factually largely out of date, since considerable source material more comprehensive than he had at his disposal has now come to light. Nevertheless, in its psychological analysis of Hitler's personality it still holds its ground among all later publications, which in many cases are based on it. However toward the end it becomes strongly polemical, which is understandable in view of the circumstances when the book was written, but mars its effectiveness. There are no such limitations to Heiden's best book, A History of National Socialism, which is of a scope astounding for its time and still highly informative.