http://www.provincia.prato.it
http://www.asi.it/
http://www.cfa.harvard.edu/researchtopics
http://www.minorplanetcenter.net/
http://irsps.sci.unich.it/
http://ssd.jpl.nasa.gov/
http://www.nasa.gov/
http://www.lpi.usra.edu/
http://meteorite.com/tektites/Tekindex.htm
http://www.alaska.net/~meteor/type.htm
http://www.lnl.infn.it/
http://nineplanets.org/offerings.html
http://www.nhm.ac.uk/