《宋史·本纪·卷十三》
奏疏上了十多遍，仁宗没有同意，才答应做皇太子，并告诫舍人说： 谨慎地守好我的屋舍，皇上有了后嗣，我就回来。 
奏十余不允，始就召，戒舍人曰： 谨守吾舍，上有适嗣，吾归矣。 
The letter was submitted more than ten times, but Ren Zong didn't agree, until he agreed to be the crown prince and warned Sheren and said: Be careful guarding my house and when his majesty has an heir, I will return.