《太平广记·卷三百九十一·铭记一》
因他讲解《周易》卜筮之事，便把郑钦悦的书信给李吉甫看，李吉甫很高兴得到这封信，高兴得超过得到宝物。
召置阁下，因讲《周易》卜筮之事，即以钦悦之书示吉甫。吉甫喜得其书。扌卡，逾获宝。
While he was explaining the Book of Changes and divination, he showed Zheng Qinyue's letter to Li Jifu. Li Jifu was overjoyed to receive the letter, more so than if he had received a precious treasure.