@inproceedings{STOC-1975-EhrenfeuchtR,
	author        = "Andrzej Ehrenfeucht and Grzegorz Rozenberg",
	booktitle     = "{Proceedings of the Seventh Annual ACM Symposium on Theory of Computing}",
	doi           = "10.1145/800116.803759",
	pages         = "117--120",
	publisher     = "{ACM}",
	title         = "{On (Un)predictability of Formal Languages}",
	year          = 1975,
}