Affiliation: | 1. Department of Mathematics, University of Glasgow, University Gardens, Glasgow G12 8QW, UK;2. School of Mathematical Sciences, Queen Mary, University of London, Mile End Road, London E1 4NS, UK;3. Institute of Mathematics, Statistics and Actuarial Science, Cornwallis Building, University of Kent, Canterbury, Kent CT2 7NF, UK;1. Italy;2. USA;3. Italy;4. Canada |