Affiliation: | 1.Institut für Angewandte Mathematik,Universit?t Bonn,Bonn,Germany;2.SFB 611,Bonn,Germany;3.BiBoS,Bielefeld-Bonn,Germany;4.CERFIM,Locarno,Switzerland;5.Acc. Arch., USI,Locarno,Switzerland;6.IZKS,Bonn,Germany;7.National Pedagogical University,Kyiv,Ukraine;8.Institute for Mathematics of NASU,Kyiv,Ukraine |