1. ARSOFT, Calle del Duero 12, Parque Científico, University of Salamanca, ARSOFT, Villamayor, Spain
2. VisualMed System Group, University of Salamanca, Salamanca, Spain
3. GRIAL Research Group, Research Institute for Educational Sciences, University of Salamanca, Salamanca, Spain
4. Dpto. Anatomía Humana University of Valladolid, Valladolid, Spain