Biyanda (''Ɓìyàndà'') and Buli (''Ɓùlì'') constitute a
Gbaya language of the Central African Republic. ''Ethnologue'' groups them as Southwest Gbaya, but it is not clear how many of the Southwest varieties are part of the same language;
Toongo and
Mbodomo, for example, are not closely related, though Toongo speakers identify ethnically as Buli, and ''Ethnologue'' also lists Mbodomo as a separate language.
References
Gbaya languages
Languages of the Central African Republic
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