Historian urges further scrutiny of Zurich art collection’s provenance A view of the E.G. Bührle collection at Zurich's Kunsthaus. Keystone/Walter Bieri Historian Raphael Gross believes that the provenance research carried out to date by the E.G. Bührle Collection Foundation is insufficient. An independent investigation led by him concluded that more clarification is needed on the provenance of the works, many of which had Jewish owners during the Second World War. 4 minutes Keystone-SDA Do you want to read our weekly top stories? Subscribe here. Gross, who is president of the German Historical Museum, and his team have scrutinised the Bührle...