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

Glottolog . http://www.glottolog.org/glottolog/

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

Mayan Languages ( pp. 39 ) . Lyle Campbell; B. Grimes (2003) · International Encyclopedia of Linguistics. 1 edited by William J. Frawley · http://tinyurl.com/jakalteko

ATLAS SOCIOLINGÜÍSTICO DE PUEBLOS INDÍGENAS EN AMÉRICA LATINA . (2009) · proeibandes http://www.proeibandes.org/atlas/tomo_2.pdf

Idiomas mayas: Número de hablantes y extension territorial . Liliana Pellicer (2005) · Revista D. Prensa Libre http://douglasvasquez.blogspot.com/2011/03/idiomas-mayas-numero-de-hablantes-y.html and http://www.monografias.com/trabajos-pdf2/guatemala-lenguas-mayas-desaparecer/guatemala-lenguas-mayas-desaparecer.pdf

México. Lenguas Indígenas Nacionales en Riesgo de Desaparición . Javier López Sánchez and Alejandra Arellano Martínez and Almandina Cárdenas Demay and Marisol Flores Castro (2012) · edited by Arnulfo Embriz Osorio and Óscar Zamora Alarcón (coordinadores) · INALI http://site.inali.gob.mx/pdf/libro_lenguas_indigenas_nacionales_en_riesgo_de_desaparicion.pdf

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) ·