[1982, “The Five Dynasties, the Song and the Yuan: the Later Period of Ascendancy of Chinese Feudalism”, in Bai Shouyi [白寿彝], editor, An Outline History of China [中国通史纲要] (China Knowledge Series)[1], Beijing: Foreign Languages Press, page 275:
In 1038, Yuanhao assumed the imperial title and called his new regime Da Xia or Great Xia, known to historians as Xi Xia or West Xia. The capital was Xingqing (Yingchuan, capital city of modern Ningxia Autonomous Region).]
