References

http://www.edu.rcsed.ac.uk/lectures/Lt12.htm

http://www-vrl.umich.edu/intro/index.html

http://library.thinkquest.org/11091/

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10175342&dopt=Abstract

http://www.hitl.washington.edu/people/hunter/wtc.pdf

http://www.nextmed.com/mmvr_virtual_reality.html