http://boris.vulcanoetna.com/

http://hvo.wr.usgs.gov/

http://www.volcano.si.edu/world/index.cfm

http://volcanoes.usgs.gov/

http://www.pbs.org/wgbh/nova/volcano/

http://learner.org/exhibits/volcanoes/

http://www.geology.sdsu.edu/

http://volcano.und.nodak.edu/