1. InriaUniv. Lille, CNRS UMR 9189 - CRIStAL, F-59000 Lille France
2. Department of Control Systems and InformaticsITMO University Saint Petersburg Russia
3. Department of MathematicsNorth Dakota State University Fargo North Dakota
4. Laboratoire des Signaux et SystémesÉcole Supérieure d'Electricité (SUPELEC) Gif‐sur‐Yvette France