Institution: | 1. IMAG and Department of Algebra, University of Granada, E18071, Granada, Spain;2. School of Computer Science, University of Birmingham, B15 2TT, Birmingham, United Kingdom;3. CITIC and Department of Algebra, University of Granada, E18071, Granada, Spain;4. CITIC and Department of Computer Science and A. I., University of Granada, E18071, Granada, Spain |