Yong-le: Year 4, Month 7, Day 18
1 Aug 1406
Imperial orders were sent to the Cheng-guo Duke Zhu Neng, regional commander of the force being sent on expedition to punish Annam. The orders read: "The weather is still hot. While the army is en route, you should provide the troops with comfort and sympathy. Do not cause them to become undisciplined."
Zhong-yang Yan-jiu yuan Ming Shi-lu, volume 11, page 830