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Leonardo da Vinci's self‐portrait drawn on paper with red chalk. The portrait was last exhibited in ‘Venaria Reale’ in 2012 in a clima‐box for 3 months and then brought to ICRCPAL for scientific analyses [Credits: Misiti, MC. (Central Institute for the Restoration of Archival and Library Heritage), ICRCPAL, Rome]. Picture by Corciulo, D. (ICRCPAL).
