《新唐书·列传·卷四》
建成往见高祖说： 秦王想抵御外寇，阻止迁都之意，是为了久掌兵权，而谋夺帝位。 
建成见帝曰： 秦王欲外御寇，沮迁都议，以久其兵，而谋篡夺。 
Jiancheng went to Gaozu and said, "The King of Qin wanted to resist foreign enemies and prevent the relocation of the capital in order to hold military power for a long time and seize the throne."