Affiliation: | 1. Department of Mathematics, University of Houston, Houston, TX 77204-3008, USA;2. Comput. and Appl. Mathematics, Rice University, Houston, TX 77005-1892, USA;3. Institute of Mathematics, University of Augsburg, D-86159 Augsburg, Germany;4. Institute of Physics, University of Augsburg, D-86159 Augsburg, Germany |