Scherg, M., Hari, R., & Hämäläinen, M. (1990). Frequency-specific sources of the auditory N19-P30-P50 response detected by a multiple source analysis of evoked magnetic fields and potentials. In S. J., Williamson, M., Hoke, G., Stroink, & M., Kotani (Eds.), Advances in biomagnetism (pp. 97-100). New York: Plenum Pr.