《魏书·列传·卷三》
返回，上奏说： 冀州土地辽阔，边界离州城六七百里，靠近海边险要遥远，应分开设置一州，镇守阻遏海湾。 
还，上言： 冀土宽广，界去州六七百里，负海险远，宜分置一州，镇遏海曲。 
Upon his return, he reported: "The state of Yu has a vast area. The border is six to seven hundred li away from the state capital, close to the sea, and the dangerous terrain is remote. A state should be established separately, guarded to block the bay.