Bibliography
Bibliography of Vitality:
Hutchinson, Noelle and Eric Johnson. 2006. "A Sociolinguistic Survey of the Ubi Language of Chad." 25. SIL International.
Bibliography of Locations:
Moseley, Christopher (ed.). 2010. Atlas of the World’s Languages in Danger, 3rd edn. http://www.unesco.org/culture/en/endangeredlanguages/atlas. (03 June, 2011.)
Bibliography of Context:
Hutchinson, Noelle and Eric Johnson. 2006. "A Sociolinguistic Survey of the Ubi Language of Chad." 25. SIL International.