Virtual humans growing up: from primary toward secondary emotions
In: KI - Künstliche Intelligenz, Jg. 2008 H. 1, S. 23-272008Estimation and children's concept of rational number size
In: Estimation and mental computation, Jg. 1986, S. 103-1111986Rational number learning aids: transfer from continuous models to discrete models
In: Focus on learning problems in mathematics, Jg. 10 H. 4, S. 1-181988Construct a sum: a measure of children's understanding of fraction size
In: Journal for research in mathematics education, Jg. 16 H. 2, S. 120-1311985On children's quantitative concept of rational number: construct and estimate the sum
In: Proceedings of the fifth annual meeting: Montréal Sept. 29 - Oct. 1, 1983 = actes de la cinquième rencontre annuelle / PME-NA, North American Chapter of the International Group for the Psychology of Mathematics Education, Jg. vol. 2, S. 272-2791983Order and equivalence of rational numbers: a clinical teaching experiment
In: Journal for research in mathematics education, Jg. 15 H. 5, S. 323-3411984Identifying fractions on number lines
In: Journal for research in mathematics education, Jg. 19 H. 3, S. 215-23219883D fixations in real and virtual scenarios
In: Journal of Eye Movement Research, Jg. 1 H. 5 (Special issue: Abstracts of the ECEM 2007), S. 13 ff.2007Evaluation of binocular eye trackers and algorithms for 3D gaze interaction in virtual reality environments
In: JVRB - Journal of Virtual Reality and Broadcasting, Jg. 5 H. 16, S. 1660 ff.2008