DJVU PDF Solnit, D.B. 1996, "Some evidence from Biao Min on the initials of Proto-Mienic (Yao) and Proto-Hmong-Mien (Miao-Yao)", in Linguistics of the Tibeto-Burman Area, vol. 19, no. 1, pp. 1-18. cite.

DJVU PDF Theraphan L. Thongkum. 1993, "A View on Proto-Mjuenic (Yao)", in The Mon-Khmer Studies Journal, vol. 22, pp. 163-230. cite.