A:All in all it looks fine. I have 2 comments:
- I think IDREF/IDREFS refer to IDs so the IMG tag in your example needs to have an "ID" attribute and you cannot refer the name as an ID in the IDREF attribute of the attribution link.
- Since the attribution text is surrounded by a link, styling wise, if there is no actual link to the copyright source it might still look as a link and will require additional styling to make it look a bit better (make the link less obvious, this is not the most important link on the page, etc).
