Del Giocondo was first named as the likeness in the painting by Italian writer Giorgio Vasari in 1550, who also dated the work at between 1503 and 1506, the university said. But because Vasari relied on anecdotal evidence, there was always doubts about the identification, and Leonardo is not known to have made any notes about the model's identity himself. Compounding the mystery, vague references in 1517, 1525 and 1540 point to other identifications.
"One possibility discussed is the presentation of a fictitious likeness of a woman; Leonardo's female ideal," the school said. But the find by Heidelberg library expert Armin Schlechter settles the matter, according to the university. In a copy of the works of Roman philosopher Cicero, a Florentine official and friend of Leonardo's wrote in the margins that da Vinci was working on a portrait of Lisa del Giocondo. The friend, Agostino Vespucci, dated his notes October 1503, also helping to pin down the exact time Leonardo was working on the painting. "All doubts as to the identity of the Mona Lisa are eliminated (by) one source," the university said. The discovery was actually made in 2005, but was not widely known until a German radio station last week aired it in a report.
