C. Drumm, J. Lemcke, and D. Oberle. The Semantic Web: Real-World Applications from Industry, volume 6 of Semantic Web and Beyond, Springer, New York, (2008)
C. Decker, T. Riedel, M. Beigl, L. de Souza, P. Spiess, J. Müller, and S. Haller. Proceedings of the 3rd IET International Conference on Intelligent Environments (IE 07), Ulm, Germany, page 40--47. Institution of Engineering and Technology (IET), London, (2007)