1. [1] J.P. Merlet: Parallel Robots (Second Edition). pp.12–17, Springer, 2006.
2. [2] SensAble Technologies: http://www.sensable.com/
3. [3] MPB Technologies: http://www.mpb-technologies.ca/
4. [4] Haption: http://www.haption.com/site/index.html
5. [5] Immersion: http://www.immersion.com/