Original sentence: Excellent examples of his work are to be found at Windsor Castle, Belvoir Castle, Montague House, Welbeck Abbey, Ham House, the Rijks Museum at Amsterdam and in the collection of Mr J Pierpont Morgan.This artist is regarded by many as the greatest painter of portrait miniatures who ever lived
Edited sentence: Magnificent examples of his work are to be found at Windsor Castle, Belvoir Castle, Montague House, Welbeck Abbey, Ham House, the Rijks Museum at Amsterdam and in the collection of Mr J Pierpont Morgan.This artist was undoubtedly the greatest painter of portrait miniatures who ever lived