McCrory, C. and R. Layte (2011). Testing Competing Models of the Strengths and Difficulties Questionnaire's (SDQ's) Factor Structure for the Parent-informant Instrument, Personality and Individual Differences, Vol. 52, Issue 8, pp. 882-887, The Netherlands: Elsevier, http://dx.doi.org/10.1016/j.paid.2012.02.011