Journal article (2011) - Peter J.H. Hulshof (author), R.J. Boucherie (author), Ingrid M.H. Vliegen (author), Maartje E. Zonderland (author), J.T. van Essen (author), E.W. Hans (author), Johann L. Hurink (author), Nikky Kortbeek (author), Nelly Litvak (author), Peter Vanberkel (author), Egbert van der Veen (author), Bart Veltman (author)