《北史·列传·卷五十三》
他带了三名骑兵，都穿上敌人的服装，晚上，他们下马偷听敌军军号的内容，发现各营如果巡夜的不按规定执行，往往被鞭打。
武从三骑，皆衣敌人衣，至暮，下马潜听其军号，历营若警夜者，有不如法者，往往挞之。
He took three cavalrymen with him, and they all put on the enemy's uniforms. At night, they dismounted to eavesdrop on the enemy's military bugles. They found that soldiers who did not follow the regulations during night patrols were often whipped.