@inproceedings{1037788,
    title = "Computer algebra systems as mathematical learning environments",
    author = "Hillel, Joel",
    year = "1993",
    pages = "45-53",
    publisher = "Εκπαιδευτήρια Δούκας",
    booktitle = "Logo-like learning environments:reflection and prospects. proceedings of the fourth European Logo Conference, University of Athens, Department of Informatics, 28-31 August 1993, Athens Greece"
}