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/

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

The status of the least documented language families in the world ( pp. 177-212 ) . Hammarström, Harald (2010) · Language Documentation and Conservation. 4 http://scholarspace.manoa.hawaii.edu/bitstream/handle/10125/4478/hammarstrom.pdf;jsessionid=76414DD90F95DF076959B1AEB0158091?sequence=1

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

Ethnologue: Languages of the World, 18th Edition . (2015) · edited by Lewis, M. Paul, Gary F. Simons, and Charles D. Fennig · SIL International http://www.ethnologue.com

Sepik languages: checklist and preliminary classification . Laycock, Donald C. (1973) · Pacific Linguistics · edited by Wurm, Stephen A. · Australian National University, Research School of Pacific Studies, Department of Linguistics

Looking Westward: Work of the Australian National University on Languages of West Irian ( pp. 68-77 ) . Don Laycock (1972) · Irian. 1 (2) ·