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) ·

Language endangerment in South America: The clock is ticking ( pp. 167-234 ) . Crevels, Mily (2012) · In The Indigenous Languages of South America: A Comprehensive Guide edited by Lyle Campbell and Veronica Grondona · Mouton de Gruyter

Ethnologue: Languages of the World, 16th Edition (2009) . (2009) · edited by M. Paul Lewis · SIL International http://www.ethnologue.com/