Jiankang (477) — the same event in Book of Southern Qi, History of the Southern Dynasties and Book of Song

Book of Southern Qi: Yang Yufu and 24 other palace attendants kill the sleeping Emperor Cangwu (Latter Deposed Emperor of Song) in a felt tent; Xiao…

What each source says

Book of Southern Qi (Nan Qishu), Annals · AD 477 · 建康

Yang Yufu and 24 other palace attendants kill the sleeping Emperor Cangwu (Latter Deposed Emperor of Song) in a felt tent; Xiao Daocheng enters the palace and directs what follows

玉夫與其黨陳奉伯等二十五人同謀，於氈屋中取千牛刀殺蒼梧王
Location: 南齊書卷1 元徽5年

History of the Southern Dynasties (Nanshi), Annals · AD 477 · 建康

Yang Yufu and others killed the Latter Deposed Emperor (Prince of Cangwu) with a qianniu sword while he slept in a felt tent (planned by Xiao Daocheng and Wang Jingze).

與萬年同入氈幄內，取千牛刀殺之
Location: 南史卷3 元徽5年

Book of Song (Songshu), Annals · AD 477 · 建康

The Later Deposed Emperor Liu Yu died in Renshou Hall at age fifteen.

七月戊子夜，帝殞於仁壽殿，時年十五。
Location: 宋書卷9 元徽5年 7月

Place: 石頭城(建康)

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