《资治通鉴·唐纪·唐纪六十》
宰相牛僧孺说： 吐蕃疆域广阔，四面边境各达一万里，失去一个维州，无损于它的国力。
牛僧孺曰： 吐蕃之境，四面各万里，失一维州，未能损其势。
Prime Minister Niu Sengru said: Tubo is vast in territory, and its borders on all four sides total 10,000 li. Losing a Weizhou would not harm its national strength.