http://www.carandclassic.co.uk/car/C262934This car mentioned in one of the posts above is advertised as a 1948 +4 which, as a model, I don't think ever existed. On a Czechoslovakian web site it is advertised as a 1939 4/4 Roadster.
It is enough to make me think it just may be a fake.
Can anyone identify it?