《资治通鉴·唐纪·唐纪五十六》
横海节度使程权认为自己世代承袭沧景节度使的职务，与河朔三镇没有区别，内心感到不安。
横海节度使程权自以世袭沧景，与河朔三镇无殊，内不自安。
Cheng Quan, the military governor of Henghai Circuit, considered himself to be the hereditary military governor of Cangjing Circuit and therefore saw himself on par with the three towns of Heshuo, which made him uneasy.