@article{SAC-OOPS-J-2005-BettiniBL,
	author        = "Lorenzo Bettini and Viviana Bono and Silvia Likavec",
	doi           = "10.5381/jot.2005.4.10.a1",
	journal       = "{Journal of Object Technology}",
	number        = 10,
	pages         = "5--29",
	title         = "{Safe and Flexible Objects with Subtyping}",
	volume        = 4,
	year          = 2005,
}