Baare WFC, Hulshoff Pol HE, Boomsma DI, Posthuma D, de Geus EJC, Schnack HG, van Haren NE, van Oel CJ, Kahn RS (2001) Quantitative genetic modeling of human brain morphology variation. Cereb Cortex, 11, 816-824.

de Geus EJC, Posthuma D, IJzerman RG, Boomsma DI (2001) Comparing blood pressure of twins and their singleton siblings: being a twin does not affect adult blood pressure. Twin Res, 4, 385-391.

Posthuma D, de Geus EJC, Boomsma DI. (2001). Perceptual speed and IQ are associated through common genetic factors. Behav Genet, 31(6), 593-602.

Posthuma D, Neale MC, Boomsma DI, de Geus EJC. (2001). Are smarter brains running faster? Heritability of alpha peak frequency, IQ and their interrelation. Behav Genet,31(6), 567-579.

Wright MJ, de Geus EJC, Ando J, Luciano M, Posthuma D, Ono Y, Hansell NK, van Baal GCM, Hiraishi K, Hasegawa T, Smith GA, Geffen GM, Geffen LB, Kanba S, Miyake A, Martin NG, Boomsma DI. (2001). Genetics of cognition: outline of a collaborative twin study. Twin Res, 4(1):48-56.