Contribution of intraoperative electrical stimulations in surgery of low grade gliomas: a comparative study between two series without (1985-96) and with (1996-2003) functional mapping in the same institution. - Duffau,H.; Lopes,M.; Arthuis,F.; Bitar,A.; Sichez,JP.; Effenterre,R Van.; Capelle,L. (J Neurol Neurosurg Psychiatry, 2005)