@inproceedings{OOPSLA-1991-Bergstein,
	author        = "Paul L. Bergstein",
	booktitle     = "{Proceedings of the Sixth Conference on Object-Oriented Programming, Systems, Languages and Applications}",
	doi           = "10.1145/117954.117977",
	editor        = "Andreas Paepcke",
	isbn          = "0-201-55417-8",
	pages         = "299--313",
	publisher     = "{ACM}",
	title         = "{Object-Preserving Class Transformations}",
	year          = 1991,
}