Topic: Attribution and lost paintings issue
Old master paintings often have a dubious attribution. These works are described by "attributed to", "workshop of", "follower of" or "manner of" in catalogues.
Maybe we can display these works separately in artwork lists under a special category as we cannot create page for an unknown artist.
For other artists, some works are only known thanks to copies of latter painters. I am specially thinking to Da Vinci, whose list on the site displays all the works related to him regardless of the attribution categories listed above. So we maybe need to create a "lost artworks" category on the artist page to display these artworks known by copies. Da Vinci's Battle of Anghiari could therefore be listed in Da Vinci's page whereas its only known depiction is from Rubens.