《旧唐书·本纪·卷九》
东都为东京，北都为北京，天下各州改为郡，刺史改为太守。
东都为东京，北都为北京，天下诸州改为郡，刺史改为太守。
The Eastern Capital to be called Tokyo, the Northern Capital to be called Beijing. All the states in the country to be renamed counties, the Cishi to be renamed Taishou.