《魏书·帝纪·卷七》
六月二日，孝文帝下诏，禁止在朝廷中讲鲜卑语，若有违反者，免去官职。
六月己亥，诏不得以北俗之语言于朝廷，若有违者，免所居官。
On the 2nd day of June, Emperor Xiaowen issued an edict forbidding Xianbei language in the court, and those violators would be dismissed from their official posts.