《周书·列传·卷二十九》
先前，北周与高齐修好，相约各自保境安民，不相侵扰。
先是，国家与齐通好，约言各保境息民，不相侵扰。
Previously, the Northern Zhou and Gao Qi had repaired their relations, agreeing to protect their own people and not interfere with each other. 