《旧唐书·本纪·卷四》
十二日，封皇第七子显为周王，迁徙改封许王素节为郇王。
庚午，封皇第七子显为周王，徙封许王素节为郇王。
On the 12th, the emperor's seventh son, Xian, was enfeoffed as the King of Zhou, and the former King of Xu, Sujie, was transferred and enfeoffed as the King of Xiun.