Affiliation: | 1. Database Laboratory, Universidade da Coruña, Spain;2. Department of Computer Science, University of Chile, Chile;1. Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil;2. Universidade Federal Fluminense, Niterói, Brazil;1. Mathematical Institute, University of Oxford, Oxford OX2 6GG, UK;2. Princeton University, Princeton, NJ 08544, USA |