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A Rapid Appraisal Language Survey of Akum . Pius Akumbu and Elizabeth Brye (2005) · http://www.sil.org/silesr/2005/silesr2005-005.pdf

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

An Atlas of Nigerian Languages . Roger Blench (2011) · Mallam Dendo http://www.rogerblench.info/Language/Africa/Nigeria/Atlas%%20of%%20Nigerian%%20Languages-%%20ed%%20III.pdf

A rapid appraisal language survey of Akum ( pp. 16 ) . Akumbu, Pius Wuchu and Brye, Elizabeth (2005) · SIL electronic survey reports (SILESR), #2005-005 · SIL International