《宋史·列传·卷三十一》
当时正谋划秋天御敌的策略，真宗诏令杨嗣和杨延昭分条列出利弊上奏，又调杨延昭任宁边军部署。
时讲防秋之策，诏嗣及延昭条上利害，又徙宁边军部署。
At that time, he was planning a strategy to defend against the enemy in the autumn. Zhenzong ordered Yang Si and Yang Yanzhao to list the pros and cons separately. Yang Yanzhao was transferred to Ningbianjun's deployment.