2006, Part of book or chapter of book (Blokland, A.A.J.; Nieuwbeerta, P. (ed.), Developmental and Life Course Studies in Delinquency and Crime: A Review of Contemporary Dutch Research, pp. 193-208)
2004, Part of book or chapter of book (Keller, S.; Velicer, W.F. (ed.), Research on the transtheoretical model: Where are we now, where are we going?, pp. 62-64)
2004, Article / Letter to editor (Jaarboek Ontwikkelingspsychologie, Orthopedagogiek en Kinderpsychiatrie, vol. 6, iss. 2004-2005, (2004), pp. 304-323)