F. Arzarello. the 24th Conference of the International Group for the Psychology of Mathematics Education (PME), 1, стр. 23--38. Hiroshima, Japan, (2000)
F. Arzarello, M. Bussi, и O. Robutti. Proceedings of the 28th International Conference of the International Group for the Psychology of Mathematics Education, 4, стр. 89-96. (2004)