[epluribus_2]

The library at Ebla, which provided us with our first historic (and non-Biblical) references to King David also provided us with messages from Celtic kings in the near Middle East to each other and to the folks at Ebla. They were written in a Celtic language Do you have a source/link for this?

[muawiyah]

I have a book published shortly after the initial forays into that library (of clay tablets), but I guess it doesn't exist without a URL, eh?!

Just do a search for "EBLA".