Mao, Tsung-wu and Chou Tsu-Yao. 1972. "A Brief Description of the Yao Language." In Miao and Yao Linguistic Studies: Selected Articles in Chinese, edited by Herbert C. Purnell. 88: 1-25. Cornell University.
Lytkin, V. I. 1966. "Komi-Permyak." In Jazyki narodov SSSR. Volume 3: Finno-ugorskie jazyki i samodijskie jazyki, edited by V. I. Lytkin and K. E. Majtinskaja. 301-315. Nauka.
Lorimer, D. L. R. 1958. "The Wakhi Language. Volume 1: Introduction, Phonetics, Grammar and Texts." School of Oriental and African Studies, W. C. I..