@inproceedings{STOC-1972-OgdenR,
	author        = "William F. Ogden and William C. Rounds",
	booktitle     = "{Proceedings of the Fourth Annual ACM Symposium on Theory of Computing}",
	doi           = "10.1145/800152.804915",
	pages         = "198--206",
	publisher     = "{ACM}",
	title         = "{Compositions of n Tree Transducers}",
	year          = 1972,
}