The Grand Scribe's Records: pt. 2. The memoirs of Han China
Qian Sima
... he established and invested the feudal lords, when King Yu 幽[Liu Yu 劉友] and King Tao-hui 悼惠[Liu Fei 劉肥] were cut off without descendants,152 Hsiao Wen Huang-ti 孝文皇帝(The Filial and Cultured August Emperor) took pity on them ...