《宋书·志·卷十七》
天子在孟月殷祭，仲月冬祭，诸侯在孟月秋祭，仲月夹祭。
天子以孟月殷，仲月烝，诸侯孟月尝，仲月袷也。
The emperor performed the Yin sacrifice in the first month, the winter sacrifice in the second month, the feudal lords performed the autumn sacrifice in the first month, and the Jia sacrifice in the second month.