Affiliation: | (1) Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Silver Street, CB3 9EW Cambridge, England;(2) Departamento de Matemática Aplicada y Computación, Universidad de Valladolid, 47005 Valladolid, Spain;(3) Wolfram Research Inc., 100 Trade Center Drive, 61820 Champaign, IL, USA;(4) Present address: Department of Mathematics, Indian Institute of Science, 560012 Bangalore, India |