《汉书·志·律历志上》
《春秋》上记载说春王正月，《左传》中解释说是周朝的正月。 大火星出现，在夏代是三月，在商朝是四月，在周朝是五月。
《经》曰 春，王正月 ，《传》曰：周正月 火出，于夏为三月，商为四月，周为五月。
The Spring and Autumn Annals records that in the first month of the Spring King's reign, the Zuo Zhuan explains that it was the first month of the Zhou Dynasty. Mars appeared in the third month in the Xia Dynasty, in the fourth month in the Shang Dynasty, and in the fifth month in the Zhou Dynasty.