《旧唐书·列传·卷九十五》
又跟随刘正臣攻破渔阳，叛将李归仁、李咸、白秀芝等前来抵抗，约经数十合战斗，将他们全都击败。不久，潼关失守，郭子仪、李光弼退兵，李忠臣便领兵北归。
又从正臣破渔阳，逆将李归仁、李咸、白秀芝等来拒战，约数十合，并摧破之；无何，潼关失守，郭子仪、李光弼退师，忠臣乃引军北归。
He also followed Liu Zhengchen to break through Yuyang. The rebel generals Li Guiren, Li Xian, Bai Xiucai and others resisted. After dozens of battles, they were all defeated. Soon, Tongguan fell, and Guo Ziyi and Li Guangbi retreated. Li Zhongchen led his soldiers back to the north.