《明史·志·卷五十一》
纳溪、白渡二盐马司，洪武五年设置，以常任官为司令，内使为司丞。
已复遣御史，其无御史者，分按察司理之。
The Naxie and Baidu salt and horse offices were established in the fifth year of Hongwu, with regular officials as commanders and eunuchs as chancellors.