@article {1664,
	title = {{Complex Question Answering: Unsupervised Learning Approaches and Experiments}},
	journal = {Journal of Artificial Intelligence Research},
	volume = {35},
	year = {2009},
	pages = {1{\textendash}47},
	author = {Y. Chali and S. R. Joty and S. A. Hasan}
}
