Laboratory of Nonlinear Systems, School of Computer and Communication Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland. Marc_Hafner@hms.harvard.edu|Laboratory of Nonlinear Systems, School of Computer and Communication Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland. Marc_Hafner@hms.harvard.edu|Laboratory of Nonlinear Systems, School of Computer and Communication Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland. Marc_Hafner@hms.harvard.edu