@inproceedings{li2008classifying,
  title={Classifying what-type questions by head noun tagging},
  author={Li, Fangtao and Zhang, Xian and Yuan, Jinhui and Zhu, Xiaoyan},
  booktitle={Proceedings of the 22nd International Conference on Computational Linguistics-Volume 1},
  pages={481--488},
  year={2008},
  organization={Association for Computational Linguistics}
}