Hu, X., Erb, M., Ackermann, A., Martin, J., Grodd, W., & Reiterer, S. (2011). Voxel-based
morphometry studies of personality: Issue of statistical model specification-effect of nuisance covariates.
NeuroImage, 54(3), 1994-2005. doi:10.1016/j.neuroimage.2010.10.024.