Wikipedia - Rusting

http://en.wikipedia.org/wiki/Rusting

Webelements - Iron

http://www.webelements.com/webelements/elements/text/Fe/key.html

Yahoo! Knowledge - Rusting

http://hk.search.yahoo.com/search/kp?ei=UTF-8&p=rusting&fr=FP-tab-web-t&meta=rst%3Dhk&fr2=tab-web