Yizhou (989) — the same event in History of Liao and Xu Zizhi Tongjian

History of Liao: He took Yizhou; the prefect Liu Chi surrendered, and the army and people were moved to Yanjing.; Xu Zizhi Tongjian: The Liao army…

What each source says

History of Liao (Liaoshi) · AD 989 · 易州

He took Yizhou; the prefect Liu Chi surrendered, and the army and people were moved to Yanjing.

甲辰,大軍齊進,破易州,降刺史劉墀,守陴士卒南遁,上帥師邀之,無敢出者。
Location: 遼史 卷12 統和7年 1月

Xu Zizhi Tongjian (Continuation of the Comprehensive Mirror) · AD 989 · 易州

The Liao army advances all together, Yi-Zhou is broken, and its prefect Liu Chi surrenders to Liao.

甲辰,遼師齊進,東京騎將夏貞顯之子仙壽先登,易州遂破,刺史劉墀降於遼。
Location: 續資治通鑑 卷014 (989년 조)

Place: 易州

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