Tang Huiyao, Vol. 72 "赤馬。與迴紇(契)苾餘沒渾同類。印行。" tr. "Horse of the Chiks, same stock as Uyghurs', (Qi)bis', Yumei-Huns'. Tamga (resembles) (character) 行." (in Chinese)
Gumilyov, L.N. Drevnie tyurki (1993:380-381). Moscow: Klyshnikov, Komarov i K°. p. cited in Tishin, V.V (2018). ["Kimäk and Chù-mù-kūn (处木昆): Notes on an Identification" https://doi.org/10.17746/1563-0110.2018.46.3.107-113] p. 107, 111