Institution: | 1. Institut de Physique Théorique, Université catholique de Louvain, B-1348 Louvain-la-Neuve, Belgium;2. Technical University of Cluj-Napoca, Department of Mathematics, str. Daicoviciu 15, RO-400020 Cluj-Napoca, Romania;3. Signal Processing Institute, Swiss Federal Institute of Technology, EPFL, Station 11, CH-1015 Lausanne, Switzerland |