^Halina Wasilewska in ed. Nathan Hill Medieval Tibeto-Burman Languages IV 2012 Page 449 "... the writing as the basis and which corresponds to the classification of the Yi languages, present day traditional Yi writing can be sub-divided into five main varieties (Huáng Jiànmíng 1993), i.e. the Nuosu, Nasu, Nisu, Sani and Azhe varieties."
^黄建明 Huáng Jiànmíng 彝族古籍文献概要 1993 Yizu guji wenxian gaiyao [Outline of classical literature of Yi nationality]. By Huang Jianming. Yunnan minzu chubanshe, 1993.