《魏书·帝纪·卷七》
八月三日，孝文帝与群臣商议 养老 制度及祭祀上帝与六位先帝的礼仪。
八月壬辰，议养老，又议肆类上帝、禋于六宗之礼，帝亲临决。
On the third day of August, Emperor Xiaowen deliberated with his courtiers on the retirement system and the ceremonies for worshiping God and the six previous emperors.