Sneezing, Yawning, Falling
Charles Nicholl: The Da Vinci Codices, 16 December 2004
“... and libricini), which he had used as source material: ten of these are lost. Some of them may yet surface: two entire notebooks were discovered by chance, in Madrid, as recently as 1967, and there have been tantalising but unconfirmed sightings of the lost treatise on light and shade known to Melzi as ‘Libro W’. The collections are ... ”