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/

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

World Oral Literature Project . http://www.oralliterature.org

Remnant Languages of Ethiopia and Sudan ( pp. 336-354 ) . M. L. Bender (1983) · In Nilo-Saharan language studies Monograph / Committee on Northeast African studies · Vol. 13 · edited by Bender, Marvin Lionel · East Lansing: African Studies Center, Michigan State University

Hozo-Sezo ( pp. 85-86 ) . Bender, Lionel M. (2007) · In Encyclopaedia Aethiopica edited by Siegbert Uhlig · Wiesbaden: Otto Harrassowitz

Mao Ethnography ( pp. 756-760 ) . Wolbert Smidt (2007) · In Encyclopedia Aethiopica edited by Uhlig, Siegbert · Otto Harrassowitz

Gumuz, Koman, Mao and Omotic ( pp. 19-21 ) . Lionel M. Bender (1985) · In Papers from the fifteenth conference on African linguistics edited by Russell G. Schuh · University of California

Sociolinguistic survey report of the Asosa - Begi - Komosha area: part II . Charlotte Wedekind and Klaus Wedekind (2002) · http://www.sil.org/resources/publications/entry/9149

Third S.L.L.E. survey on languages of the Begi/Asosa area . Wedekind, Charlotte and Klaus Wedekind and Ralph Siebert (2002) · http://www.sil.org/silesr/abstract.asp?ref=2002-056

A general description of Mao ( pp. 166-225 ) . Baye Yimam (2006) · Ethiopian Languages Research Centre (ELRC) Working Papers. 2 (2) ·