《明史·本纪·卷二十二》
七月十日，松潘副使李忠臣约总兵官杨愈懋谋划收复永宁，没有攻克，双双战死。
秋七月甲辰，松潘副使李忠臣约总兵官杨愈懋谋复永宁，不克，皆死之。
On July 10, Songpan Deputy Envoy Li Zhongchen and Commander-in-Chief Yang Yuyumao planned to retake Yongning, but failed to conquer it and both died in battle.