《汉书·传·景十三王传》
令封宪王儿子刘平三万户，为真定王；子刘商三万户，为泗水王。 
其封宪王子平三万户，为真定王；子商三万户，为泗水王。 
Order the king's son Liu Ping to be named the King of Zhending with 30,000 households; and his son Liu Shang to be named the King of Sishui with 30,000 households.