Using soviet topographic maps ?

I’m just wondering if it’s permitted to use the old topographic maps found on sites like poehali.org for Eastern Europe.
I’ve read the section found here:
http://wiki.openstreetmap.org/wiki/Out-of-copyright_maps

and it says - "Operators of these sites often claim a new copyright for their scans. Whether this is valid, or whether arguments similar to those in Bridgeman v Corel would apply, is arguable and may well vary by jurisdiction. "

So does that mean that it’s forbidden to use these maps?

Definitely don’t use these maps. At the time, Russia hadn’t signed the Berne Convention on copyright, and it seems likely that some of these maps were themselves therefore copied from other (copyrighted) maps. There’s great debate about whether the UK ones contain Ordnance Survey copyrighted material, for example - see http://www.SovietMaps.com/ for more.