@article{VLDB-2014-ShuaiYYC13,
	author        = "Hong-Han Shuai and De-Nian Yang and Philip S. Yu and Ming-Syan Chen",
	ee            = "http://www.vldb.org/pvldb/vol7/p253-shuai.pdf",
	journal       = "{Proceedings of the VLDB Endowment}",
	number        = 4,
	pages         = "253--264",
	title         = "{Willingness Optimization for Social Group Activity}",
	volume        = 7,
	year          = 2013,
}