《资治通鉴·唐纪·唐纪五十七》
都知兵马使刘悟，即唐肃宗朝平卢节度使刘正臣的孙子。李师道命悟率兵万余人屯驻阳，以拒抗官军。
都知兵马使刘悟，正臣之孙也，师道使之将兵万馀人屯阳谷以拒官军。
Liu Wu, the military governor, was the grandson of Liu Zhengchen, the military governor of Pingu during the reign of Emperor Suzong of Tang Dynasty. Li Shidao ordered Wu to lead more than ten thousand troops to garrison Yanggu to resist the imperial army.