@inproceedings{IFL-2005-WeeldenSP,
	author        = "Arjen van Weelden and Sjaak Smetsers and Rinus Plasmeijer",
	booktitle     = "{Revised Selected Papers of the 17th International Workshop on Implementation and Application of Functional Languages}",
	doi           = "10.1007/11964681_9",
	isbn          = "3-540-69174-X",
	pages         = "142--159",
	publisher     = "{Springer International Publishing}",
	series        = "{Lecture Notes in Computer Science}",
	title         = "{Polytypic Syntax Tree Operations}",
	volume        = 4015,
	year          = 2005,
}