How is rape defined?

George Galloway sparked outrage with his comments on the Assange case, but does the definition of rape vary significantly between countries?

Source: http://www.bbc.co.uk/news/magazine-19333439#sa-ns_mchannel=rss&ns_source=PublicRSS20-sa

duchenne muscular dystrophy john elway ethan allen packers green bay packers