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Sar at Ethnologue (18th ed., 2015) (subscription required)
(in French) Fournier, Maurice, Les consonnes du sar, dans Études phonologiques tchadiennes (Jean-Pierre Caprile, éd.), pp. 37-44, Paris, SELAF, 1977, ISBN2-85297-019-8
Keegan, John M. (2014). Lexique Sar. The Eastern Sara Languages: Cuenca: Morkeg Books.
(in French) Moundo Ndimajibay, Nei-Balway, Les limites des modifications en sar, dans Études phonologiques tchadiennes (Jean-Pierre Caprile, éd.), pp. 45-58, Paris, SELAF, 1977, ISBN2-85297-019-8