@article{articlec3e0fb64,
title   = {An algorithm for automatic checking of exercises in a dynamic geometry system: iGeom},
author = {Isotani, Seiji and Brandão, Leônidas de Oliveira},
year = {2008},
doi = {10.1016/j.compedu.2007.12.004},
publisher = {Elsevier},
journal   = {Computers & Education}
}