Institution: | 1. Department of Applied Mathematics , Illinois Institute of Technology , Chicago, IL 60616, USA;2. Département de Mathématiques , Université d'évry Val d'Essonne , 91025 évry Cedex, France;3. School of Mathematics , University of New South Wales , Sydney, NSW 2052, Australia;4. Faculty of Mathematics and Information Science , Warsaw University of Technology , 00-661 Warszawa, Poland |