@inproceedings{SIGMOD-1977-WongE,
	author        = "Kai C. Wong and Murray Edelberg",
	booktitle     = "{Proceedings of the Seventh ACM SIGMOD International Conference on Management of Data}",
	cdrom         = "SIGMOD77/P168.PDF",
	doi           = "10.1145/509404.509431",
	pages         = "168",
	publisher     = "{ACM}",
	title         = "{Interval Hierarchies and Their Application to Predicate Files}",
	year          = 1977,
}