《史记·七十列传·卫将军骠骑列传》
过了一年，公孙贺以左将军的身份两次跟随大将军从定襄出兵打匈奴，没有功劳。
後一岁，以左将军再从大将军出定襄，无功。
A year later, as a general of the left, he accompanied the grand general twice in leading the troops out of Dingxiang to attack the Huns, but he did not make any significant achievement.