《宋书·志·卷十二》
推算弦望时月亮位置：在合朔位置的度上加九十八，大分上加一千二百七十九，小分上加三十四，按照前面的方法处理各数字满相应数的情况，就能得到上弦时月亮位置，如法再加就可依次得到望、下弦、下一次合朔时的位置。
推弦望月所在度：加合朔度九十八，大分千二百七十九，小分三十四，数满命如前，即上弦月所在度也。又加得望下弦后月合也。
Calculating the position of the moon at the time of the first and last quarters: Add ninety-eight to the degree at the time of conjunction, add one thousand two hundred and seventy-nine to hundreds, add thirty-four to fractions, and calculate the remainder as in the previous method; the position of the moon at the time of the first quarter is obtained; the positions of the moon at the time of the last quarter, new moon, and conjunction can be obtained by adding in the same way.