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For the second part of his series on slums, Paul Mason asks if they are here forever.
BBC World Service Online
The world's slums are booming - so what can they teach us about enterprise and community?
Filthy and embarrassing, the Ganges needs help - we explore how the Thames can save it
We visit western Hungary and find out how the area hit by toxic sludge is recovering
Claims that China leads the green revolution at home, but lags behind abroad