《资治通鉴·唐纪·唐纪三十》
张九龄斥责了牛贵儿，并把这些话告诉了玄宗，玄宗因此有所感悟，所以一直到张九龄罢相，太子的地位没有动摇。
九龄叱之，以其语白上；上为之动色，故讫九龄罢相，太子得无动。
Zhang Jiuling reprimanded Niu Guier and told these words to Xuanzong. As a result, Xuanzong realized his mistakes and the position of Crown Prince remained unshakable until he resigned as prime minister.