@inproceedings{LATA-2007-FrancezK,
	author        = "Nissim Francez and Michael Kaminski",
	booktitle     = "{Proceedings of the First International Conference on Language and Automata Theory and Applications}",
	pages         = "7--26",
	publisher     = "{Research Group on Mathematical Linguistics, Universitat Rovira i Virgili, Tarragona}",
	title         = "{Pushdown automata with cancellation and commutation-augmented pregroups grammars}",
	volume        = "Report 35/07",
	year          = 2007,
}