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3. Straub, M., Riener, A., and Ferscha, A. (2009, January 16–18). Route guidance with a vibro-tactile waist belt. Proceedings of the 4th European Conference on Smart Sensing and Context, Guildford, UK.
4. Degeler, A. (2021, January 08). FeelSpace Uses Vibrating Motors to Help the Blind Feel the Right Direction. Available online: https://thenextweb.com/eu/2015/12/17/feelspace-helps-blind-feel-right-direction-vibrating-motors/.
5. Yelamarthi, K., Haas, D., Nielsen, D., and Mothersell, S. (2010, January 1–4). RFID and GPS integrated navigation system for the visually impaired. Proceedings of the 2010 53rd IEEE International Midwest Symposium on Circuits and Systems, Seattle, WA, USA.