@inbook {MATHEDUC.02342594,
    author       = {Campbell, Stephen R.},
    title        = {A new method for research in computer-based learning environments.},
    year         = {2001},
    booktitle    = {Proceedings of the 25$^{th}$ Conference of the International Group for the Psychology of Mathematics Education. Vol. 1},
    isbn         = {90-74684-16-5},
    pages        = {389},
    publisher    = {,},
    msc2010      = {U50xx},
    identifier   = {2001f.05526},
}