1. National Institute for Resources and Environment, Japan, http://www.nire.go.jp/eco_tec_e/hyouka_e.htm.
2. http://icon.rice.edu/
3. http://www.snirc.org/
4. http://www.nanotechproject.org/
5. http://www.defra.gov.uk/corporate/consult/nanotech-vrs/index.htm