Was Leonardo da Vinci's famous anatomical chart actually a collaborative effort? smithsonianmag.com
excerpt
When Sgarbi took a look at it, he discovered, to his amazement, that in fact it contained almost the full text of the Ten Books, along with 127 drawings. Moreover, it showed every sign of having been produced during the late 1400s, years before anyone was known to have systematically illustrated the work. “I was totally astonished,” Sgarbi told me. But then he made what he calls “a discovery within the discovery”