Chinese President Xi Jinping (back, 3rd L) and his wife Peng Liyuan (front) visit a tulip exhibition, accompanied by Dutch King Willem-Alexander (back, 2nd R) and Queen Maxima (back, 1st R) , at Keukenhof in Lisse, the Netherlands, March 23, 2014. Peng was invited to christen a new strain of tulip the "Cathay" here on Sunday. [Photo/Xinhua]