Experience already gained in operations in the Balkans and in Russia enabled the Germans to devise more effective antiguerilla measures than had their Italian predecessors. With the forces at hand, they set out to contain the guerillas and keep up the flow of bauxite and other strategic raw materials produced in the Balkans to the German war machine. http://www.army.mil/cmh-pg/books/wwii/antiguer-ops/AG-BALKAN.HTM#yugo2