@inproceedings{ML-1989-VanLehn,
	author        = "Kurt VanLehn",
	booktitle     = "{Proceedings of the Sixth International Workshop on Machine Learning}",
	isbn          = "1-55860-036-1",
	pages         = "215--217",
	publisher     = "{Morgan Kaufmann}",
	title         = "{Discovering Problem Solving Strategies: What Humans Do and Machines Don’t (Yet)}",
	year          = 1989,
}