《新唐书·列传·卷一百四十三》
皇帝派延王持节到太原，对克用说： 不用你的建议，致有今日之难。
帝使延王持节至太原，谓克用曰： 不用卿计，故逮此，无可言者。
The emperor sent Yan Wang to go to Taiyuan with a message and said to Ke Yu, "I didn't use your advice, and this is why I'm in this difficult position now."