1. Department of Neurosurgery, Puerta de Hierro University Hospital, Madrid, Spain
2. Independent Medical Translator, Jekintown, PA, USA
3. Pathologisch-anatomische Sammlung Im Narrenturm - NHM, Vienna, Austria
4. Statistics Department, Computing Center, CSIC, Madrid, Spain
5. Department of Neurosurgery, La Princesa University Hospital, Madrid, Spain