《资治通鉴·唐纪·唐纪六十六》
按以前的惯例，南诏的使者见唐朝的节度使，要在院庭伏拜行礼，董成等人声称： 南诏骠信已应天顺人，自为君主，我见贵国节度使应当分庭抗礼。 
故事，南诏使见节度使，拜伏于庭，成等曰： 骠信已应天顺人，我见节度使当抗礼。 
According to the previous conventions, the envoys of Nanzhao, when meeting the governors of Tang, should kneel down and bow in the courtyard, but Dong Cheng and others claimed that: the "Biao Xin" of Nanzhao had agreed with God's will and wish of the people, and established himself as the sovereign, thus we should meet your country's governor on an equal footing.