《宋史·本纪·卷四十六》
宝元年正月初一，下诏立为皇子，改赐今名。
宝祐元年正月庚辰，诏立为皇子，改赐今名。
On the first day of the first month of the Bao era, an imperial edict was issued to establish him as the crown prince, and his name was changed to his current one.