佛祖統紀 45.31

45.31

（歐陽外傳云。公至圓通。范文正公以書抵永叔。問孫子闕疑。魏武不注。師就覽畢。即取別幅釋之。公驚汗永夕）。

(The *Ouyang waizhuan* states: When the Lord arrived at Yuantong, Lord Fan Wenzheng sent a letter to Yongsbu, asking about the unresolved doubts in *Sunzi* which Cao Cao did not annotate. As soon as the Master finished examining it, he took another sheet and explained it. The Lord broke into a cold sweat for the entire night).