Xuan-de: Year 4, Month 3, Day 24
27 Apr 1429
The eunuchs Yun Xian and Xu Liang, who had been sent as envoys to the external yi, were recalled. Earlier Yun Xian and so on had received orders to proceed separately to the external yi to sway and instruct them. These two persons were constantly disposed to envious hatred and they both induced the local officials to engage in feuding and killing and to obstruct and hinder the other envoy. At this time, the Emperor heard of the events and both were recalled.
Zhong-yang Yan-jiu yuan Ming Shi-lu, volume 18, page 1256