Cotter, John. "States in Guatemala and el Salvador on the Eve of Spanish Conquest." In Hall, Carolyn and Héctor Pérez Brignoli, Historical Atlas of Central America. Norman, University of California Press, 2003.

Cotter, John. "States in Guatemala and el Salvador on the Eve of Spanish Conquest." In Hall, Carolyn and Héctor Pérez Brignoli, Historical Atlas of Central America. Norman, University of California Press, 2003.