《资治通鉴·梁纪·梁纪十四》
东魏的高欢对李延孙的存在感到忧虑，多次派遣部队攻打他，都没有取得功。
东魏高欢患之，数遣兵攻延孙，不能克。
Gao Huan of the Eastern Wei was worried about Li Yansun's existence and repeatedly sent troops to attack him, but failed to achieve any results.