《资治通鉴·后晋纪·后晋纪五》
郭威看到刘知远有忧虑之色，对他说： 河东地方山川险要坚固，风俗崇尚勇武，此地多产战马，安静的时候勤于农业生产，动乱的时候勇于练习军事，这是成就霸业和王道的依凭，有什么可忧虑的。 
郭威见知远有忧色，谓知远曰： 河东山河险固，风俗尚武，士多战马，静则勤稼穑，动则习军旅，此霸王之资也，何忧乎！ 
Guo Wei saw that there was a gloomy look on Liu Zhiyuan’s face, and said to him: “Hedong is a land with steep and formidable mountains and rivers, and the locals are warlike, and there are many warhorses here; during peaceful times, they devote themselves to agriculture, and in times of chaos, they are fervent about military training, this is the foundation for building hegemony and undertaking the kingly way, what’s there to worry about?”