@inproceedings{STOC-1998-KupfermanV,
	author        = "Orna Kupferman and Moshe Y. Vardi",
	booktitle     = "{Proceedings of the 30th Annual ACM Symposium on Theory of Computing}",
	doi           = "10.1145/276698.276748",
	isbn          = "0-89791-962-9",
	pages         = "224--233",
	publisher     = "{ACM}",
	title         = "{Weak Alternating Automata and Tree Automata Emptiness}",
	year          = 1998,
}