Alexander

You asked

> [A]
> Do you mean O.Trubachev's book "Indoarica v Severnom

Prichernomorie"?

> Yes, the distance between pre-Cimmerian times and today is about 3-

3.5 millennia. But Trubachev relies mainly on ancient and partly
medieval toponyms and personal names. Only very few of them survived
till our days. If only they were available for investigations I think
nobody could prove their Indo-Aryan origin. So I think that in this
example the time of the _reliable surviving_ should be shortened till
the Greek or Roman times, i.e. about 1.000 years.

> On the other hand the Ukrainian steppes were a very inconvenient

place for preserving archaic toponyms - so often nation changed
there, and as a rule with a great violence, when the old population
disappeared very quickly.

I haven't read anything academic on this subject. I came across it a
couple of years ago in a detailed discussion on Cybalist.

Regards

John