《新唐书·列传·卷一百四十一》
不久，吐谷浑归顺，禄东赞怨恨，率精兵攻打。吐谷浑大臣素和贵逃奔吐蕃，告诉国内虚实，所以吐蕃能破其国。
未几，吐谷浑内附，禄东赞怨忿，率锐兵击之，而吐谷浑大臣素和贵奔吐蕃，槊以虚实，故吐蕃能破其国。
Shortly after, Tuyuhun submitted to the Tang dynasty, and Lukdongzan was resentful, leading an elite force to attack. Tuyuhun Prince Su Hegui escaped to Tubo and informed them of the real situation in his country, whereupon Tubo was able to conquer it.