《贞观政要·卷八·论贡赋》
贞观十二年，西域的疏勒、朱俱波、甘棠国派使者向唐太宗进献特产。唐太宗对各位大臣说： 如果天下不安定，南方的日南、西域各国的朝贡使者怎么会源源不断进入京城呢？
贞观十二年，疏勒、朱俱波、甘棠遣使贡方物，太宗谓群臣曰： 向使中国不安，日南、西域朝贡使亦何缘而至？
In the twelfth year of the Zhenguan reign, the Shule, Zhujubo, and Gantang countries from the Western Regions sent envoys to Tang Taizong to present their specialties. Tang Taizong said to the ministers: If the world is not in peace, how can the tribute envoys from Rinan in the south and the various countries in the Western Regions enter the capital one after another?