**Author details**

Massimo Zucco<sup>1</sup> \*, Marco Pisani<sup>1</sup> and Tiziana Cavaleri<sup>2</sup>

\*Address all correspondence to: m.zucco@inrim.it

1 National Institute of Metrological Research, Strada delle Cacce, Turin, Italy

2 Centre for Conservation and Restoration La Venaria Reale, Venaria Reale, Province of Turin, Italy
