Artist of original: (?) Giuseppe Nogari
Artist of original: Allegretto Nuzi
Artist of original: Jakob Ochtervelt
Artist of original: Isaac Oliver I
Artist of original: Orcagna
Artist of original: School of Orcagna
Artist of original: Silvestro dei Gherarducci
Artist of original: Deodato Orlandi
Artist of original: Bernard van Orley
Artist of original: Adriaen van Ostade
Artist of original: Albert van Ouwater
Artist of original: School of Dieric Bouts
Artist of original: Juriaen Ovens
Artist of original: Anthonie Palamedesz.