@inproceedings{HCI-EI-1999-ScharKK,
	author        = "Sissel Guttormsen Schär and Johannes Kaiser and Helmut Krueger",
	booktitle     = "{Proceedings of the Eighth International Conference on Human-Computer Interaction. Volume 1: Ergonomics and User Interfaces}",
	isbn          = "0-8058-3391-9",
	pages         = "456--460",
	publisher     = "{Lawrence Erlbaum}",
	title         = "{Multimedia: the Effect of Picture, Voice & Text for the Learning of Concepts and Principles}",
	year          = 1999,
}