Suiyang (757) — the same event in Old Book of Tang, New Book of Tang and Zizhi Tongjian

Old Book of Tang: Yin Ziqi took Suiyang and killed Zhang Xun, Yao Gan and Xu Yuan.; New Book of Tang: The army of An Qingxu took Suiyang; Xu Yuan…

What each source says

Old Book of Tang (Jiu Tangshu), Annals · AD 757 · 睢陽

Yin Ziqi took Suiyang and killed Zhang Xun, Yao Gan and Xu Yuan.

癸丑,賊將尹子奇陷睢陽,害張巡、姚訚、許遠。
Location: 舊唐書 卷10 至德2年

New Book of Tang (Xin Tangshu), Annals · AD 757 · 睢陽

The army of An Qingxu took Suiyang; Xu Yuan, the prefect, along with Zhang Xun and Nan Jiyun and others died for their country.

癸丑,安慶緒陷睢陽,太守許遠及張巡
Location: 新唐書 卷006 肅宗·代宗 至德2年10月

Zizhi Tongjian (Comprehensive Mirror) · AD 757 · 睢陽

When Hao arrived, Suiyang had already fallen three days earlier.

比鎬至,睢陽城已陷三日。
Location: 권220 757년 항

Place: 睢陽

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