@inproceedings{ICALP-2001-HarjuIKS,
	author        = "Tero Harju and Oscar H. Ibarra and Juhani Karhumäki and Arto Salomaa",
	booktitle     = "{Proceedings of the 28th International Colloquium on Automata, Languages and Programming}",
	doi           = "10.1007/3-540-48224-5_48",
	isbn          = "3-540-42287-0",
	pages         = "579--590",
	publisher     = "{Springer-Verlag}",
	series        = "{Lecture Notes in Computer Science}",
	title         = "{Decision Questions Concerning Semilinearity, Morphisms, and Commutation of Languages}",
	volume        = 2076,
	year          = 2001,
}