《宋书·志·卷十二》
于是就改变了正朔，更换了历法的有关数据，用具有卓越才能、学贯古今的人，编制了《太初历》，校验中气和朔日的偏差以使闰分准确，观察山星所在度数以考证推算的精度，以建寅的月份的朔日为止朔，以黄钟对应的月份为历的开始。
于是改正朔，更历数，使大才通人，造《太初历》。校中朔所差，以正闰分；课中星得度，以考疏密，以建寅之月为正朔，以黄钟之月为历初。
So Zhengshuo was changed, the relevant data of the calendar was changed, and a person with outstanding talents and knowledge of ancient and modern times was used to compile the "Taichu Calendar", to verify the deviation of the middle and first qi to make the intercalation accurate, to observe the degree of the mountain star to test the calculation The accuracy of the degree, the first day of the month when Jianyin is used as the first day of the month, and the month corresponding to Huangzhong as the beginning of the calendar.