A fine arts museum in Belgium has returned a painting to the heirs of a German Jewish couple who had their property stolen by the Nazi regime before World War II. ‘Blumenstilleben,’ (Still Life with Flowers) painted in 1913 by German artist Lovis Corinth, was among dozens of artworks stolen by the Nazis from Gustav and Emma Mayer. The couple fled Frankfurt to Belgium in 1938, and later settled in the UK. After the war, the painting of pink flowers in a blue vase was exhibited in Belgium’s Royal Museums of Fine Arts because the authorities at the time failed...