1. Institute of Information Theory and Automation of the Czech Academy of Sciences Pod Vodárenskou věží 4 182 00 Prague 8 Czech Republic
2. Department of Philosophy Faculty of Philosophy University of Barcelona Carrer de Montalegre 6 08001 Barcelona Spain
3. Department of Mathematics and Applied Mathematics University of Pretoria Private Bag X20 Hatfield Pretoria 0028 Republic of South Africa