@inproceedings{DLT-1993-AtanasiuM,
	author        = "Adrian Atanasiu and Victor Mitrana",
	booktitle     = "{Proceedings of the First International Conference on Developments in Language Theory}",
	isbn          = "981-02-1645-9",
	pages         = "51--59",
	publisher     = "{World Scientific}",
	title         = "{Substitution on Words and Languages}",
	year          = 1993,
}