A specialist investigated 400 cultural relics held by overseas collectors that were originally at Yuanmingyuan, the Old Summer Palace, Beijing Morning News reported on Tuesday.
Liu Yang, a member of Yuanmingyuan Society of China, described his research and investigation into the relics in his just published book.
However, he said the chances of these works returning to China are slim.
Recently, eight carved stone relics were returned to Yuanmingyuan, arousing public's attention again, the report said.