Is each fact referenced with an appropriate, reliable reference? - Yes her page is filled with 245 notes, 11 secondary source references and 22 "further readings"
Is everything in the article relevant to the article topic? Is there anything that distracted you? -The article seems to include relevant information about the artist. The order of topics are positioned well too.
Is the article neutral? Are there any claims, or frames, that appear heavily biased toward a particular position? -No, in areas such as her political stance, relationships and art works the authors have properly cited sources and stayed away from personal commentary.
Where does the information come from? Are these neutral sources? If biased, is that biased noted? - Information comes from biographies about Yoko and newspapers and magazines. All information that I have read is unbiased.
Are there viewpoints that are overrepresented, or underrepresented? - With a big emphasis on her art career, and an ample section on her relationship and the Beatles I feel that it is an accurate representation of information that specifically relates to her.
Check a few citations. Do the links work? Is there any close paraphrasing or plagiarism in the article? -Two sources didn't have a link, but all the linked articles took me directly to the source or an ISBN number. I ran the article through a plagiarism checker and according to it there was 23% unique content, so there's a good deal that most of the content is plagiarized .
Is any information out of date? Is anything missing that could be added? I haven't researched much on this artist nor have I heard any recent news on her, but the article informs us of events that have happened in 2014 so I would conclude that it is up to date for the most part.