@inproceedings{DLT-2012-FlickK,
	author        = "Nils Erik Flick and Manfred Kudlek",
	booktitle     = "{Proceedings of the 16th International Conference on Developments in Language Theory}",
	doi           = "10.1007/978-3-642-31653-1_40",
	isbn          = "978-3-642-31652-4",
	pages         = "452--458",
	publisher     = "{Springer International Publishing}",
	series        = "{Lecture Notes in Computer Science}",
	title         = "{On a Hierarchy of Languages with Catenation and Shuffle}",
	volume        = 7410,
	year          = 2012,
}