《资治通鉴·唐纪·唐纪七》
李世民让长孙无忌秘密地将房玄龄等人召来，房玄龄等人说： 敕书的旨意是不允许我们大家再事奉秦王的。如果我们现在私下去谒见秦王，肯定要因此获罪致死，因此我们不敢接受秦王的教令！ 
世民令无忌密召房玄龄等，曰： 敕旨不听复事王；今若私谒，必坐死，不敢奉教。 
Li Shimin ordered Changsun Wuji to secretly call up Fang Xuanling and others, Fang Xuanling and others said: The emperor’s edict does not allow us to serve King Qin any more. If we go to see King Qin privately now, we will definitely be sentenced to death for this reason, so we do not dare to accept King Qin’s order! 