Affiliation: | (1) Departement Mathematik, ETH-Zentrum, 8092 Zürich, Switzerland;(2) Department of Mathematics, University of Minnesota, 127 Vincent Hall, 206 Church St. S.E., Minneapolis, MN 55455, USA;(3) Departments of Electrical Engineering and of Mathematics, Technion, Israel Institute of Technology, Haifa, 32000, Israel |