《魏书·帝纪·卷一》
率领部族南迁大泽，大泽方圆千余里，土地苍茫辽阔，地势低洼湿润。
南迁大泽，方千余里，厥土昏冥沮洳。
Led the tribes southward into Dazhi, which was estimated to cover an area of 1,000 square li, with vast desolate lands and low-lying wetlands.