@inproceedings{popescu-aleven-koedinger:2004:COLING,
  author    = {Popescu, Octav  and  Aleven, Vincent  and  Koedinger, Kenneth},
  title     = {Understanding Students' Explanations in Geometry Tutoring },
  booktitle = {Proceedings of Coling 2004 },
  editor = {},
  year      = 2004,
  month     = {Aug 23--Aug 27},
  address   = {Geneva, Switzerland},
  publisher = {COLING},
  pages     = {1339--1345}
}