《资治通鉴·唐纪·唐纪三十八》
刘清潭将诏书递给可汗，说道： 先帝虽然驾崩，但是现今的皇上已经即位，皇上就是过去的广平王，曾与叶护共同收复两京。 
清潭致敕书曰： 先帝虽弃天下，今上继统，乃昔日广平王，与叶护共收两京者也。 
Liu Qingtan hands the edict to the Khagan and said: "Although the former emperor passed away, the present emperor has already ascended the throne. He is the former Prince of Guangping who, along with Yehu, recovered the two capitals."