There was one about 6 months ago where there is a article about a books character and there were some facts about this character presented that came from no where with no source. The original author of the book came on to correct the page (being the definitive source on the character) and they could not get the article changed because there wasn't a written source and even when the author did create one it was rejected and the false facts remained.

Was frustrating to read about but it follows issues I have had trying to fix problems in some technology articles as well. Its not just an issue with biographies and politics there is basically a troll behind every false fact on wikipedia with power.