1. A conflict of visions: ideological origins of political struggles;T Sowell,2002
2. Perennial library;E Hoffer,1966
3. A single communal faith?: the German Right from Conservatism to National Socialism;T Rohkramer,2007
4. Hitler and the Rise of the Nazi Party;F McDonough,2012
5. History of Europe;E Britannica,2014