《周书·本纪·卷五》
这年，北齐的常山王高演废黜皇帝高殷而自立为皇帝，这就是孝昭帝。
是岁，齐常山王高演废其主殷而自立，是为孝昭帝。
In that year, Prince Changshan of Northern Qi, Gao Yan, deposed Emperor Gao Yin and proclaimed himself emperor. This was Emperor Xiaozhao.