@inproceedings{TAPSOFT-1997-BonoBDL,
	author        = "Viviana Bono and Michele Bugliesi and Mariangiola Dezani-Ciancaglini and Luigi Liquori",
	booktitle     = "{Proceedings of the Seventh International Joint Conference on Theory and Practice of Software Development}",
	doi           = "10.1007/BFb0030619",
	isbn          = "3-540-62781-2",
	pages         = "465--477",
	publisher     = "{Springer}",
	title         = "{Subtyping Constraints for Incomplete Objects (Extended Abstract)}",
	year          = 1997,
}