Hong-wu: Year 23, Month Intercalary 4, Day 3
17 May 1390
The Guang-xi Provincial Administration Commission memorialized that the country of Annam had sent an envoy to offer tribute. The Emperor spoke to Li Yuan-ming, the Minister of Rites, saying: "Annam is situated on a distant coast. They took the lead in showing loyalty and yearly bring local products as tribute. I bear in mind that they know how to look up to and emulate China and admire our culture. However, why do they offer tribute so frequently? Previously, the various foreign countries offered tribute once every year. But, as the transport was difficult and it caused hardship for the people, I ordered that they come to Court once every three years. Now, Annam is not following these instructions and has again come to offer tribute. You, Minister of Rites, must quickly order Guang-xi to send them home, and require them to come but once every three years."
Zhong-yang Yan-jiu yuan Ming Shi-lu, volume 7, page 3011