Neuronavigation combined with electrophysiological monitoring for surgery of lesions in eloquent brain areas in 42 cases: a retrospective comparison of the neurological outcome and the quality of resection with a control group with similar lesions - Reithmeier, T; Krammer, M; Gumprecht, H; Gerstner, W; Lumenta, C B (Minim Invasive Neurosurg, 2003)