《元史·列传·卷二》
太宗于元年夏还京，八月即皇位。第二年秋，太宗伐金，命拖雷率军同行，破天城堡，拔蒲城县，渡黄河攻凤翔。太宗三年破洛阳、河中诸城。攻下凤翔后，有个降于蒙古军的金国人叫李昌国的对拖雷说： 金朝迁都汴梁，所依恃的是黄河、潼关的天险。
凤翔既下，有降人李昌国者言： 金主迁汴，所恃者黄河、潼关之险尔。
Taizong returned to the capital in the summer of the first year and ascended to the throne in August. In the autumn of the second year, Taizong attacked the Jins and ordered Tuo Lei to lead the troops together, besieging Tiancheng Fort, capturing Pucheng County, and crossing the Yellow River to attack Fengxiang. Taizong captured Luoyang, Hezhong, and other cities in the third year. After capturing Fengxiang, a Jin citizen who had surrendered to the Mongol army called Li Changguo told Tuo Lei: "The capital of the Jin Dynasty moved to Bianliang, and they relied on the Yellow River and Tongguan's natural danger."