《资治通鉴·齐纪·齐纪三》
于是，孝文帝下令尚书李冲挑选饱学之士和裴昭明等人辩论。李冲推荐了著作朗上谷人成淹。
魏主命尚书李冲选学识之士与之言，冲奏遣著作郎上谷成淹。
As a result, Emperor Xiaowen ordered the Minister of State Li Chong to select men who were erudite and debate with Pei Zhaoming and others. Li Chong recommended the author from Shànggǔ, Cheng Yan.