Chang'an (820) — the same event in Old Book of Tang, New Book of Tang and Zizhi Tongjian

Old Book of Tang: Emperor Xianzong died at the age of 43 at Zhonghe Hall in Daming Palace (there is a theory that he was assassinated by the eunuch…

What each source says

Old Book of Tang (Jiu Tangshu), Annals · AD 820 · 長安

Emperor Xianzong died at the age of 43 at Zhonghe Hall in Daming Palace (there is a theory that he was assassinated by the eunuch Chen Hongzhi).

是夕,上崩於大明宮之中和殿,享年四十三。
Location: 舊唐書 卷15 元和15年 1月

New Book of Tang (Xin Tangshu), Annals · AD 820

Emperor Xianzong died; the eunuch Chen Hongzhi and others were implicated.

庚子,皇帝崩,年四十三
Location: 新唐書 卷007 德宗·順宗·憲宗 元和15年1月

Zizhi Tongjian (Comprehensive Mirror) · AD 820 · 長安

Emperor Xianzong suddenly dies at Zhonghe Hall.

庚子,暴崩於中和殿。
Location: 資治通鑑 卷241

Place: 長安

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