1. Dey , A. K. Abowd , G. D. 1999 Towards a better understanding of context and context-awareness www.it.usyd.edu.au/∼bob/IE/99-22.pdf
2. Drost , C. 2004 Privacy in context aware systems. University of Twente, Enschede, Netherlands, Department of Informatics, Federal University of Espirito Santo, Vitoria, Brazil http://asna.ewi.utwente.nl/assignments/completed/drost.pdf
3. Tatli , E. I. 2006 Context data model for privacy www.prime-project.eu/events/standardisation-ws/positionpapers/cdmfp.pdf
4. Location sensing and privacy in a context-aware computing environment