Inherit Attribute from Parent if not blank

I think you need to use the |= operator instead of =. Essentially the logic of the former is as you describe. I’d put in an aTbRef link if i didn’t have the site in maintenance just know.

If in doubt about using, make a small test TBX - you’ll only need five or six notes to test: a prototype, the container and a note with and without $Authors data.