《北史·本记·卷十一》
六月初五，下诏说，初受命为帝时，有赤雀降临的祥瑞，以五德相生推算，应是火的颜色。
六月癸未，诏以初受命，赤雀降祥，推五德相生，为火色。
On the fifth of the sixth month, an imperial edict was issued stating that when he first received the mandate of heaven, there was the auspicious sign of a red sparrow. Based on the theory of the mutual generation of the Five Elements, it should be the color of fire.