Affiliation: | 1. MAP5 CNRS 8145, Université de Paris, 45 rue des Saints-Pères, 75270, Paris cedex 06, France;2. Lab VC-170, Baruch College of CUNY, One Baruch way, NY, NY 10010, USA;3. Department of Mathematics, National Technical University of Athens, 9 Iroon Polytechneiou Str., 15780, Athens, Greece |