@InProceedings{heilman-et-al-2008,
  title={{Retrieval of Reading Materials for Vocabulary and Reading Practice}},
  author={Heilman, Michael and Zhao, Le and Pino, Juan and Eskenazi, Maxine},
  booktitle={The Third Workshop on Innovative Use of NLP for Building Educational Applications. Association for Computational Linguistics.},
  year={2008}
}