《周书·列传·卷三十三》
可汗心情凄惨了很久，说： 好在没有什么可疑虑的，应当共同平定束方的贼寇，然后嫁出我的女儿。 就下令杨荐先回去覆命，再请求向东征讨。
可汗惨然良久曰： 幸无所疑，当共平东贼，然后发遣我女。 乃令荐先报命，仍请东讨。
The khan was very saddened for a long time and said, "Fortunately, there is nothing to worry about. We should work together to pacify the rebels in the east and then marry my daughter off." So he ordered Yang Jian to go back and report first, and then requested to go east to quell the rebellion.