Beatriz Garza Cuaron and Doris Bartholomew. Languages of intercommunication in Mexico. In: Stephen Adolphe Wurm, Peter Mühlhäusler, Darrell T. Tyron (1996), Atlas of languages of intercultural communication in the Pacific (1622 pages), pp. 1254–1290. Chapter 2. Historical outline, p. 1258, 2.1.5: Replacement of the dominant indigenous languages by Spanish, pp. 1260–1262. Chapter 4: Spanish as a language of intercommunication, from the Conquest to present. pp. 1270–1271.
Rainer Enrique Hamel: Bilingual Education for Indigenous Communities in Mexico. Encyclopedia of Language and Education (2008), Part 5, Part 18, pp. 1747–1758.
Juan Carlos Godenzzi: Language Policy and Education in the Andes. Encyclopedia of Language and Education (2008), Part 1, Part 4, pp. 315–329.