《后汉书·本纪·显宗孝明帝纪》
十二月二十六日，明帝诏令说： 现在正是春天，人们都忙于耕田养蚕。
十二月甲寅，诏曰： 方春戒节，人以耕桑。
On the twenty-sixth day of December, Emperor Ming issued an edict saying: It is now spring, and people are busy farming and raising silkworms.