@article{143077,
      author = {Zimmermann, Walter, and Cunningham, Steve,},
      url = {http://library.usi.edu/record/143077},
      title = {Visualization in teaching and learning mathematics : a  project /},
      publisher = {Mathematical Association of America,},
      recid = {143077},
      pages = {224 p., [4] p. of plates :},
      address = {[Washington, D.C.] :},
      year = {1991},
}