1. Westkämper, E.; Hummel, V.; Rönnecke, T., 2005, The Stuttgart Enterprise Model Integrated Engineering of Strategic & Operational Functions. In: IEMS Proceedings, March 14–16, Cocoa Beach, Florida USA, p. 379–384.
2. Weiser M., 1991, The Computer for the Twenty-First Century, In: Scientific American, 09/91, p. 94–110.
3. Westkämper, E.; Jendoubi, L.; Eissele, M.; Ertl, T., 2006, Smart Factory-Bridging the gap between digital planning and reality. In: Manufacturing Systems 35, No. 4, p. 307–314.
4. Sonderforschungsbereich 627 Nexus-Umgebungsmodelle für mobile kontextbezogene Anwendungen, Available at: http://www.nexus.unistuttgart.de/, 24.01.2008.
5. Hazas, M., Ward, A., 2002, A Novel Broadband Ultrasonic Location System, In: Ubicomp 2002 Proceedings, September 29–October 1, Göteborg, Sweden, Springer Verlag, p. 264–280.