《资治通鉴·唐纪·唐纪五十六》
适值官军包围青陵，切断了郾城的退路，郾城守将邓怀金去找董昌龄商议，董昌龄便规劝他归顺朝廷。于是，邓怀金向李光颜请求投降说： 郾城将士的父母、妻子、儿女都住在蔡州，请您前来攻打郾城，我点燃烽火向蔡州请求援救，等援救的兵马来到郾城时，您便迎击他们，蔡州兵马必定失败。此后我再归降，郾城将士的父母、妻子、儿女大约便能够幸免于死了。 
会官军围青陵，绝郾城归路，郾城守将邓怀金谋于昌龄，昌龄劝之归国，怀金乃请降于李光颜曰： 城人之父母妻子皆在蔡州，请公来攻城，吾举烽求救，救兵至，公逆击之，蔡兵必败，然后吾降，则父母妻子庶免矣。 
As it happened, the government forces surrounded Qingling, which cut off Yanshi's escape route; the defending general of Yanshi, Deng Huaijin, sought to confer with Dong Changling, so Dong Changling advised him to submit to the Court. Accordingly, Deng Huaijin asked Li Guangyan to surrender, saying: "The fathers, wives, and children of the generals and soldiers of Yanshi all live in Cai Zhou, please come and attack Yanshi, while I light a beacon to request aid from Cai Zhou; when the relief force arrives at Yanshi, you should fight them and the Cai Zhou forces will surely be defeated. After this, I will surrender, such that the parents, wives, and children of the generals and soldiers of Yanshi will be spared."