The Bua language is spoken by some 7,708 people (as of 1993) north of the Chari River around Korbol and Gabil; it is the largest member of the small Bua subgroup of the Mbum-Day subgroup of the Adamawa languages. It is mutually comprehensible with Fanian. The Chari or Shari River is a 949-kilometer-long river of Chad into Lake Chad. ... The Bua languages are a subgroup of the Mbum-Day subgroup of the Adamawa languages spoken in southern Chad. ...
Bibliography
P. A. Benton, Languages and Peoples of Bornu Vol. I, Frank Cass & Co:London 1912 (1st ed.)/1968 (2nd ed.) Gives Barth's unpublished vocabulary of Bua on pp. 78-130.
M. Gaudefroy-Demombynes, Documents sur les langues de l'Oubangui-Chari, Paris, 1907. Includes (pp. 107-122) a 200-word comparative list of Bua, Niellim, Fanian, and Tunia, with a brief grammar and some phrases collected by Decorse.
J. Lukas, Zentralsudanisches Studien, Hamburg, Friedrichsen, de Gruyter & Cie, 1937. Gives the wordlists of Nachtigal, zu Mecklenburg, Barth, and Gaudefroy-Demombynes for Bua (~400 words), Niellim (~200 words), and Koke (~100 words).
A. N. Tucker & M. A. Bryan, The Non-Bantu Languages of North-Eastern Africa, Handbook of African Languages, part III, Oxford University Press for International African Institute, 1956. Summarizes the grammar of Bua and two relatives based on existing fieldwork.
The Bualanguages are a subgroup of the Mbum-Day subgroup of the Adamawa languages spoken by fewer than 30,000 people in southern Chad in an area stretching roughly between the Chari River and the Guera Massif.
All of these languages are tonal, with distinctive vowel length and nasal vowels in limited contexts.
Most of these languages have lost the typical Niger-Congo noun class system (Goula Iro appears to have retained it to some degree.) However, its former presence is betrayed by their quite complicated system of plural formation, combining internal ablaut with changes to final consonants and/or suffixation.