Affiliation: | 1. Department of Computer Science, King’s College London, London WC2R 2LS, UK;2. Université Paris-Est, France;3. Department of Computer Science, University of Western Ontario, N6A 5B7, London, Ontario, Canada;4. Institute of Informatics, Warsaw University, ul. Banacha 2, 02-097 Warszawa, Poland;5. Department of Mathematics and Informatics, Copernicus University, Torun, Poland |