Institution: | 1. Aix-Marseille Université, CNRS, Centrale Marseille, LATP, UMR 7353, 39 Rue F-Joliot-Curie, 13453 Marseille Cedex 13, France;2. Mathematics Institute, ?itná 25, 11567 Prague 1, Czech Republic;3. Mathematics Institute, Silesian University at Opava, Na Rybní?ku 1, 74601 Opava, Czech Republic |