@inproceedings{SIGIR-2011-LiuB,
	author        = "Jingjing Liu and Nicholas J. Belkin",
	booktitle     = "{Proceedings of the 34th International ACM SIGIR Conference on Research and Development in Information Retrieval}",
	doi           = "10.1145/2009916.2010110",
	isbn          = "978-1-4503-0757-4",
	pages         = "1183--1184",
	publisher     = "{ACM}",
	title         = "{Search task difficulty: the expected vs. the reflected}",
	year          = 2011,
}