《明史·志·卷五十六》
三年，夏原吉因北京官吏、军队、工匣的粮饷不能支付，分条上呈预备策，说： 以粮换盐的旧有规则太重，商人很少来换盐，请求重新制定。 
三年，原吉以北京官吏、军、匠粮饷不支，条上预备策，言： 中盐旧则太重，商贾少至，请更定之。 
In the third year, as the grain and money for officials, the army, and workshops in Beijing had not been paid, Xia Yuangji submitted a proposal in a separate clause, saying: The old rules for exchanging grain for salt were too strict, so few merchants came to exchange for salt, and he requested to revise them.