Zaro-Weber, O., Moeller-Hartmann, W., Heiss, W.-D., & Sobesky, J. (2010). A simple positron emission tomography-based calibration for perfusion-weighted magnetic resonance maps to optimize penumbral flow detection in acute stroke. Stroke, 41(9), 1939-1945. doi:10.1161/STROKEAHA.110.584029.