Hirt, U. [P:(DE-HGF)0] ; Kreins, P. [P:(DE-HGF)0] ; Kuhn, U. [P:(DE-HGF)0] ; Mahnkopf, J. [P:(DE-HGF)0] ; Venohr, M. [P:(DE-HGF)0] ; Wendland, F. [P:(DE-Juel1)VDB4997]