《汉书·纪·高帝纪下》
皇帝下诏说： 诸侯之子弟在关中的，免除十二年赋役，已归还原籍的，免除六年赋役。
诏曰： 诸侯子在关中者，复之十二岁，其归者半之。
The emperor decreed: “Sons and younger brothers of the feudal princes in Guanzhong are exempted from 12 years of corvée labor, and those who have already returned to their own native places are exempted for 6 years.”