《资治通鉴·周纪·周纪三》
赵王便亲自登门解释说： 我国东面有齐国、中山国；北面有燕国、东胡；西面是楼烦，与秦、韩两国接壤，如果没有骑马射箭的训练，怎么能守得住呢？
王自往请之，曰： 吾国东有齐、中山，北有燕、东胡，西有楼烦、秦、韩之边。今无骑射之备，则何以守之哉？
The King of Zhao personally went to visit him and explained: To the east of our country is Qi and Zhongshan, to the north is Yan and Donghu, to the west is Loufan, and we border Qin and Han. If we don’t practice archery on horseback, how can we possibly defend ourselves?