《资治通鉴·汉纪·汉纪十八》
赵充国派人到四望峡侦察，发现峡中并无敌兵。夜晚，赵充国率军穿过四望峡，抵达落都山，召集各位军校、司马说道： 我知道羌人不懂用兵之法了。
遣骑候四望峡中无虏，夜，引兵上至落都，召诸校司马谓曰： 吾知羌虏不能为兵矣！
Zhao Chongguo sent someone to reconnoiter the Siwang Gorge and found that there were no enemy soldiers in the gorge. At night, Zhao Chongguo led the army through the Siwang Gorge and arrived at Luodu Mountain. He summoned all the military officers and prefects and said: I know that the Qiang people do not know how to fight.