Each art work has, on its back, an authenticity certificate, in Italian language. On the same certificate is declared that the art works are the original works of Nino Gorni, and there is a registration code collected in our register here in Italy. In this certificate there is the explanation about Nino Gorni monogram, a sort of signature on the paint; this monogram identify the type of subjects that are elaboration of art works derived from ancient existing paintings.