Bretscher, N; (2009) Dynamic Geometry Software: the teacher’s role in facilitating instrumental genesis. In: Durrand-Guerrier, V and Soury-Lavergne, S and Arzarello, F, (eds.) Proceedings of the Sixth Congress of the European Society for Research in Mathematics Education:CERME 6. (pp. pp. 1340-1348). European Society for Research in Mathematics Education: Lyon, France. Green open access