@inproceedings{HCI-EI-1999-MaggioniR,
	author        = "Christoph Maggioni and Hans Röttger",
	booktitle     = "{Proceedings of the Eighth International Conference on Human-Computer Interaction. Volume 1: Ergonomics and User Interfaces}",
	isbn          = "0-8058-3391-9",
	pages         = "301--305",
	publisher     = "{Lawrence Erlbaum}",
	title         = "{Virtual Touchscreen — a novel User Interface made of Light — Principles, metaphors and experiences}",
	year          = 1999,
}