《宋书·志·卷十二》
求第二天：每天加一度，分上不加，经过斗宿时则在分上减去斗分，如分比斗分小则减一度在分数上加纪法后再减。
求次日，日加一度，分不加，经斗除斗分，分少退一度。
To seek the next day: Add one degree each day, do not add to the minutes, subtract the number of minutes in the Dou constellation when passing Dou constellation, and if the minutes are less than the Dou minutes, subtract one degree, add the Ji method to the minutes and then subtract.