Rockville Centre, N.Y.: Sarpedon, 2000. Urner, Klaus. "Let's Swallow Switzerland": Hitler's Plans Against the Swiss Confederation. Lanham, Md.: Lexington Books, 2001. Vagts, Detlev F. "Switzerland, International Law and World War II." The American Journal of International Law 91.3 (July 1997), 466–475. Weinberg, Gerhard L. A World at Arms: A Global History of World War II. 2nd Edition. New York: Cambridge University Press, 2005. Weinberg, Gerhard L. "German Plans and Policies Regarding Neutral Nations in World War II with Special Reference to Switzerland." German Studies Review 22.1 (February 1999), 99–103. Williamson, Gordon. Gebirgsjäger: German Mountain Trooper, 1939–1945. Oxford: Osprey, 2003. Williamson, Gordon. German Mountain & Ski Troops, 1939–1945. Oxford: Osprey, 1996. External links Andreas P. Herren, Tannenbaum 1940. A Swiss site with research about the Swiss and German operational planning as well as maps and charts. "Operation Tannenbaum." An overview of the military planning, and a counterfactual examination of a German invasion. Stephen P. Halbrook, "Target Switzerland." A lecture promoting Halbrook's book on Axis plans against Switzerland. "Switzerland's Neutrality: Did Switzerland prolong World War II?." The question, extent, and effect of Switzerland's neutrality in World War II. Abandoned projects of Nazi Germany Tannenbaum Switzerland in World War II Tannenbaum Cancelled military operations of World War II Germany–Switzerland relations Italy–Switzerland relations Cancelled military operations involving Italy