《新唐书·列传·卷五十》
张说心中明白太平公主等人心怀阴谋，于是派使者向玄宗献上一把佩刀，请皇帝迅速决策。皇帝接纳了他的建议。
说知太平等怀逆，乃因使以佩刀献玄宗，请先决策，帝纳之。
Zhang Shuo knew that Princess Taiping had a conspiracy in mind, so he sent an envoy to present a sword to Emperor Xuanzong and asked the emperor to make a quick decision. The emperor accepted his suggestion.