《资治通鉴·唐纪·唐纪五十八》
裴度当初奉命征讨幽州和成德时，回鹘国请求出兵参战，朝廷商议以后，认为不可，于是，穆宗派宦官出使制止。
裴度之讨幽、镇也，回鹘请以兵从。朝议以为不可，遣中使止之。
When Pei Du was ordered to attack Youzhou and Chengde, the Huihe state requested to send troops to participate in the war. After deliberation, the court considered it inappropriate, so Muzong sent an eunuch to stop it.