1. Attitudes, personality and behavior;Ajzen,1988
2. Likert scales and data analyses;Allen;Quality Progress,2007
3. The midpoint on a five-point Likert-type scale;Armstrong;Perceptual and Motor Skills,1987
4. Construction versus choice in cognitive measurements;Bennet,1993
5. Biemans, H. J. A. (1997). Fostering activation of prior knowledge and conceptual change (Doctoral dissertation). Katholieke Universiteit Nijmegen, Nijmegen. Available from http://opc.ubn.ru.nl/.