Chang'an (763) — the same event in Old Book of Tang, New Book of Tang and Zizhi Tongjian

Old Book of Tang: The Tibetans entered Chang'an and set up Guangwu Prince Chenghong as emperor.; New Book of Tang: The Tibetans took the capital…

What each source says

Old Book of Tang (Jiu Tangshu), Annals · AD 763 · 長安

The Tibetans entered Chang'an and set up Guangwu Prince Chenghong as emperor.

戊寅,吐蕃入京師,立廣武王承宏為帝,仍逼前翰林學士於可封為制封拜。
Location: 舊唐書 卷11 廣德1年

New Book of Tang (Xin Tangshu), Annals · AD 763 · 長安

The Tibetans took the capital, Chang'an, and set up Li Chenghong, Prince of Guangwu, as emperor.

戊寅,吐蕃陷京師,立廣武郡王承宏為皇帝
Location: 新唐書 卷006 肅宗·代宗 廣德1年10月

Zizhi Tongjian (Comprehensive Mirror) · AD 763 · 長安

In 763 (Wuyin day), Tubo enters Chang'an; Gao Hui, together with Tubo's general Ma Zhongying, sets up as emperor Chenghong, Prince of Guangwu and grandson of the former Prince of Bin Shouli, adopts a reign title and establishes the officials.

戊寅,吐蕃入長安,高暉與吐蕃大將馬重英等立故邠王守禮之孫廣武王承宏為帝,改元,置百官,以前翰林學士於可封等為相。
Location: 권223 763년 항

Place: 長安

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