1. Department of Mining, Industrial and ICT Engineering, Polytechnic University of Catalonia (UPC), Manresa, Barcelona, Spain
2. Department of Business Organization, Polytechnic University of Catalonia (UPC), Manresa, Barcelona, Spain
3. Department of Mathematics, Polytechnic University of Catalonia (UPC), Manresa, Barcelona, Spain
4. Mineria per al Desenvolupament, Manresa, Barcelona, Spain