@inproceedings{SIGMOD-1989-HullS,
	author        = "Richard Hull and Jianwen Su",
	booktitle     = "{Proceedings of the 19th ACM SIGMOD International Conference on Management of Data}",
	cdrom         = "SIGMOD89/P147.PDF",
	doi           = "10.1145/67544.66940",
	pages         = "147--158",
	title         = "{On Accessing Object-Oriented Databases: Expressive Power, Complexity, and Restrictions}",
	year          = 1989,
}