Hot Enamel on metal (tell my)

[North]

Maybe there are people who have experienced with the technique of "hot enamel on metal"

There is a series of paintings made of metal, has a relief pattern, ie, the surface is not flat, very cleverly handed dawn, color-shadow (one picture is very heavy and a meter in width and length, others less), on the back is done in Yugoslavia, Hand Made, DEKOR ZAGREB, author's signature - in the paintings depicted the castle (or fortress, the monastery). At present, no image will be in June ...
can someone just come across? He knows where to look, what resources?
Paintings were purchased in Moscow in 70 years, at that time very, very expensive, a single copy.
   
If someone experienced in those years with a similar, share information.
I would be very grateful (for spaces of the Russian Internet but found nothing)

In June (or July) must lay out images for the evaluation (not on sale) and get some useful information.

Things are not replicable (in principle, even be it three times, Chinese) on the technique of execution and quality, plus a country anymore.