《逸周书·卷六·周月解》
到商汤时候，向夏桀用兵，消除百姓灾难，顺应天意革夏之命。改换正朔，变化服饰，区别称号，形式与内容，以示不相沿袭。以斗柄指丑位为正月，变更百姓的视听，顺应天时的大变，也是一代的大事。
其在商汤，用师于夏，除民之灾，顺天革命，改正朔，变服殊号，一文一质，示不相沿，以建丑之曰为正，易民之视。
When it came to Shang Tang's time, he used soldiers against Xia Jie, eliminated the people's suffering, and followed the will of heaven to reform Xia's life. He changed the first month of the year, changed the clothes, and distinguished the titles, form and content, in order to show that they were not passed on from each other. Taking the Big Dipper pointing at the Ugly position as the first month, changing the people's sight and hearing, and adapting to the great changes in the seasons, is also a major event of a generation.