Wendland, F. [P:(DE-Juel1)VDB4997] ; Berthold, G. [P:(DE-HGF)0] ; Fritsche, J.-G. [P:(DE-HGF)0] ; Herrmann, F. [P:(DE-Juel1)141774] ; Kunkel, R. [P:(DE-Juel1)VDB4996] ; Voigt, H.-J. [P:(DE-HGF)0] ; Vereecken, H. [P:(DE-Juel1)129549]