A. de Assis, M. Danchak, und L. Polhemus. CLIHC '05: Proceedings of the 2005 Latin American conference on Human-computer interaction, Seite 289--294. New York, NY, USA, ACM Press, (2005)
C. Mosch, R. Anderl, und A. Moura. Proceedings of ASME International Mechanical Engineering Congress and Exposition (IMECE2010), Vancouver, British Columbia, Canada, Volume 3: Design and Manufacturing, Parts A and B, Seite 363-370. ASME, (2010)