Site violates Google's quality guidelines - Can't figure out why
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I am at a loss!
Our website has been delisted due to "Site violates Google's quality guidelines" and "We've reviewed your site and we still see links to your site that violate our quality guidelines. Specifically, look for possibly artificial or unnatural links pointing to your site that could be intended to manipulate PageRank.".

After months of cleaning up backlinks and jumping through hoops, we re-submitted and have yet again been knocked back.

HOW can I identify which links Google is penalising us for?
Is there some sort of tool that can provide hints as to which links I should review?