Mariotti, M. A., Falcade, R., Laborde, C., (2003). Function and Graph in a DGS environment. Proceedings of the 2003 Joint Meeting of PME and PMENA, Eds. Pateman N.A., Dougherty, B.J., Zilliox J. vol. 3, pp. 237-244, Honolulu, CRDG, College of Education, University of Hawai'i, (USA). ISSN 0771-100X.