《资治通鉴·后唐纪·后唐纪五》
当时，契丹人曾多次侵略边境，所以朝廷在幽、易之间驻扎了大量军队。对于军队将领们的行动，王都暗地里都有所防备，时间长了逐渐产生了猜疑。
时契丹数犯塞，朝廷多屯兵于幽、易间，大将往来，都阴为之备，浸成猜阻。
At that time, the Khitan had invaded the border many times, so the imperial court stationed a large number of troops between You and Yi. Wang Du was secretly on guard against the actions of the military leaders. Over time, he gradually became suspicious.