《隋书·列传·卷五十》
于是毒杀杨浩，在魏县自立为帝，国号许，改元天寿，设置文武百官。
于是鸩杀浩，僭皇帝位于魏县，国号许，建元为天寿，署置百官。
So he poisoned Yang Hao and established himself as emperor in Weixian, with the national name Xu, changed his reign name to Tianshou, and set up civil and military officials.