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) ·

Ethnologue: Languages of the World, 16th Edition (2009) . (2009) · edited by M. Paul Lewis · SIL International http://www.ethnologue.com/

Narrow Bantu 'J' ( pp. 116-119 ) . Barbara Grimes (2003) · In International Encyclopedia of Linguistics edited by William Frawley · Oxford University Press

A comparative study of the Bantu and semi-Bantu languages ( pp. xi, 819, map; xii, 544 ) . Johnston, Harry Hamilton (1919/22) · Clarendon Press

Prosodologie et phonologie non linéaire ( pp. 463 ) . Jouannet, Francis (1985) · Linguistique générale, #1 · Agence de Coopération Culturelle et Technique (ACCT); Soc. des Etudes Linguistiques et Anthropologiques de France (SELAF)