Yong-le: Year 1, Month 6, Day 12
1 Jul 1403
...the Supervising Secretary Yang Chun and others, a total of 12 people, were sent separately as chief and deputy envoys to promulgate Imperial proclamations in the various countries, including Annam and Siam. They were also to confer variegated silks upon the kings of these places.
Zhong-yang Yan-jiu yuan Ming Shi-lu, volume 10, page 0384/86