@inproceedings{HT-2005-AtzenbeckN,
	author        = "Claus Atzenbeck and Peter J. Nürnberg",
	booktitle     = "{Proceedings of the 16th Conference on Hypertext and Hypermedia}",
	doi           = "10.1145/1083356.1083368",
	isbn          = "1-59593-168-6",
	pages         = "63--65",
	publisher     = "{ACM}",
	title         = "{Constraints in spatial structures}",
	year          = 2005,
}