Wichmann, Soren (2006). “Mayan Historical Linguistics and Epigraphy: A New Synthesis”. 《Annual Review of Anthropology》 35: 279–294. doi:10.1146/annurev.anthro.35.081705.123257.
Shapiro, Judith (1987). “From Tupã to the Land without Evil: The Christianization of Tupi-Guarani Cosmology”. 《American Ethnologist》 1 (14): 126–139. doi:10.1525/ae.1987.14.1.02a00080.
ethnologue.com
Gordon, Raymond G., Jr. (Ed.). (2005). Ethnologue: Languages of the World (15th ed.). Dallas, Texas: SIL International. ISBN1-55671-159-X. (Online version: http://www.ethnologue.com)