@inproceedings{CHI-1991-Singley,
	author        = "Mark K. Singley",
	booktitle     = "{Proceedings of the Ninth ACM SIGCHI Conference on Human Factors in Computing Systems}",
	doi           = "10.1145/108844.108992",
	isbn          = "0-89791-383-3",
	pages         = "439--440",
	publisher     = "{ACM}",
	title         = "{MOLEHILL: an instructional system for Smalltalk programming}",
	year          = 1991,
}