Endangered Languages Catalogue Project. Compiled by research teams at University of Hawai'i Mānoa and Institute for Language Information and Technology (LINGUIST List) at Eastern Michigan University . (2012) ·

Endangered Languages in Central Africa ( pp. 163-178 ) . Bruce Connell (2007) · In Language Diversity Endangered edited by Matthias Brenzinger · Mouton de Gruyter

Africa ( ch. 7 ) . Gerrit J. Dimmendaal and F. K. Erhard Voeltz (2007) · In Encyclopedia of the World's Endangered Languages edited by Christopher Moseley · Routledge

Atlas of the World’s Languages in Danger . Christopher Moseley (ed.) (2010) · UNESCO Publishing http://www.unesco.org/culture/en/endangeredlanguages/atlas

Le gèmé ou jèmé, une nouvelle langue du groupe zande ( pp. 67-85 ) . Boyd, Raymond and Nougayrol, Pierre (1988) · In Lexique comparatif des langues oubanguiennes edited by Moñino, Yves · Libr. Orientaliste Paul Geuthner; Laboratoire de Langues et Civilisations à Tradition Orale (LACITO); Dépt. Languages et Parole en Afrique Central (LAPAC)