《隋书·列传·卷三十五》
新罗国曾派使者上贡，子雄在朝廷上与使者交谈，因而问起新罗国冠制的由来。
新罗尝遣使朝贡，子雄至朝堂与语，因问其冠制所由。
Silla sent an envoy to pay tribute, and Zixiong talked with the envoy at the court, so he asked about the origin of Silla's crown system.