Affiliation: | 1. Department of Applied Mathematics, Illinois Institute of Technology Chicago, IL 60616, USA;2. Econometrisch Instituut, Erasmus Universiteit, P.O. Box 1738, 3000 DR Rotterdam, The Netherlands;3. Department of Mathematical Sciences, Clemson University, Clemson, SC, USA;4. Department of Mathematics, University of Louisville, Louisville, KY 40292 USA |