According to http://blog.stackoverflow.com/2012/04/when-a-site-grows-quiet/, data dumps of closed-down sites are available under the same CC BY-SA license as other data dumps. However, since the original content (and their owners) have been removed, what satisfies the Attribution part of that license?
That is, to what, specifically, do site e.g. attempting to resurrect answers.onstartups.com pages have to link to?
Jeff Atwood wrote in '10 at Correct attribution is impossible for failed sites:
It's probably fine in this case to link back to the proposal
However, for the specific site in question, it had no proposal, and all the original pages have been deleted. What does satisfy the attribution part in this case?