http://masfoundations.org/wiki/TWiki/bin/view.cgi/Main/WebRss
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with the name of the web:
http://masfoundations.org/wiki/TWiki/bin/view.cgi/Main/WebRss
http://masfoundations.org/wiki/TWiki/bin/view.cgi/Sandbox/WebRss
http://masfoundations.org/wiki/TWiki/bin/view.cgi/TWiki/WebRss