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

Sociolinguistic survey report for the Blé language ( pp. 23 ) . Berthelette, Carol and Berthelette, John (2001) · SIL electronic survey reports (SILESR), #2001-001 · SIL International http://www.sil.org/silesr/2001/001/Ble.pdf

A survey on language death in Africa ( pp. 402 ) . Sommer, Gabriele (1992) · In Language death: factual and theoretical explorations with special reference to East Africa Contributions to the sociology of language, #64 · edited by Brenzinger, Matthias · Mouton de Gruyter

Field Report on Jalkunan (Personal Communication) . Vu Truong (2012) ·

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) ·