《新唐书·列传·卷七十八》
当时堂兄杲卿任常山太守，杀了叛军将领李钦凑等人，清除了土门的敌人，十七个郡同一天自动归顺朝廷，推举真卿任盟主，有二十万兵力，截断了燕赵的交通联络。
是时，从父兄杲卿为常山太守，斩贼将李钦凑等，清土门。十七郡同日自归，推真卿为盟主，兵二十万，绝燕、赵。
At that time, his elder cousin, Gaoqing, was the Magistrate of Changshan. He killed the rebel general Li Qinchou and others, purging away the enemies in Tumen, causing seventeen different commanderies to spontaneously submit to the court on the same day. They elected Zhenqing as their盟主, and he had 200,000 soldiers under his command, cutting off all communications between Yan and Zhao.