Zheng-tong: Year 4, Month 11, Day 7
12 Dec 1439
As the army on expedition against Lu-chuan was consuming much grain and there was again a shortage of rice, merchants were called to the granaries of Da-li Prefecture and the Jin-chi Command in Yun-nan to buy Si-chuan well salt for grain. At Da-li, one yin of salt was to be sold for one dou five sheng of rice, while in Jin-chi, each yin of salt was to be sold for one dou of rice. These payments were not to be subject to the usual payment precedence.
Zhong-yang Yan-jiu yuan Ming Shi-lu, volume 24, page 1160/61