《资治通鉴·唐纪·唐纪二十七》
群臣认为宋王李成器等人地位逼近皇帝，便请玄宗按照历朝的惯例放他们到地方任刺史。
群臣以成器等地逼，请循故事出刺外州。
The ministers felt that Duke Song Li Chengqi and the others were close in status to the emperor, so they asked Xuanzong to move them to the provinces based on past imperial practices.