item should not include both
item contains two elements which mean the same thing. This can occur in RSS 2.0 when you mix core elements and namespace elements. This can confuse news aggregators and RSS parsers, since there are no universally accepted rules about which element takes precedence.
item elements that mean the same thing:
author and dc:creator
category and dc:subject
source and dc:source
Remove one of the duplicate elements.
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