Kognitive Kategorien
In: GWAI / Proceedings: German Workshop on Artificial Intelligence, Jg. vol. 13, S. 482-4831989Order and equivalence of rational numbers: a cognitive analysis
In: Journal for research in mathematics education, Jg. 16 H. 1, S. 18-361985Order and equivalence of rational numbers: a clinical teaching experiment
In: Journal for research in mathematics education, Jg. 15 H. 5, S. 323-3411984On 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. 272-2791983