Plus: major lots announced for the London modern art sales
Plus: Dreweatts and Mallett sold, and dealers on the move in London
Plus: art fair shake-ups in Germany and an Ottoman art record in London
The auction houses have announced their top lots for the May sales in New York
Early reported sales at TEFAF Maastricht were strong, particularly among Old Master dealers
Overseas buyers drove high prices at London's Impressionist and modern sales
