This is not a Volpini...and to prove it, I can show you an encyclopedia where it was called...Volpini!
That was the origin of the mistake. It's an enciclopedia of the seventies, called Milleruote. The car was known like that when it was discovered in the late sixties, it but it's not.
It's was later correctly identified as a Zanussi.
It is now in Nicolis' Museum and you can read all its story in Zanussi's website.
It was built by Fioravante Zanussi with an Alfa Romeo 6c 1750 engine with two cilinders cut out (used in a previous siluro by Zanussi). The engine was later replaced by a BMW 319 and finally a Fiat 1100 unit.