Balster, T. [P:(DE-Juel1)VDB9873] ; Tautz, F. S. [P:(DE-Juel1)128791] ; Polyakov, V. [P:(DE-HGF)0] ; Ibach, H. [P:(DE-Juel1)VDB5414] ; Schaefer, J. A. [P:(DE-HGF)0]