<<Disclaimer: Verify this information before applying it to your situation.>>

This is a direct quote:

"This isn't the answer to your question, but descending gluten content
order:  spelt, wheat, kamut, rye, oats, barley, buckwheat"

How can Buckwheat contain gluten if it's not technically a grain?
From everything I've read, Buckwheat is gluten free.  It may present
a problem if it is grown in the same fields as wheat.  Otherwise,
it is safe for celiacs.

Is there proof to the contrary?  (Please, no anecdotal information)