《北史·列传·卷八十五》
有官吏上奏说 ：九国不怕遥远艰险，自远方进贡地方特产，应当与他们互通，怎么能事先压制呢？ 
有司奏： 九国不惮遐险，远贡方物，当与其进，安可豫抑后来？ 
An official submitted a memorial, saying: "The Nine Nations are not afraid of the distance and difficulties, and they come from afar to pay tribute with local specialties. We should communicate with them. How can we suppress them in advance?"