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↑Mooser, F.; Meyer-Abich, H. and McBirney, A. R. (1958). Catalogue of the Active Volcanoes of the World, VI. International Volcanological Association, Naples. p. 146.
↑Rose, W. I. Jr.; Stoiber, R. E. (1969). The 1966 eruption of Izalco volcano, El Salvador. J. Geophys. Res., 74. pp. 3119-3130.
↑Sheets P. D. (2004). Apocalypse then: social science approaches to volcanism, people, and cultures in the Zapotitan Valley, El Salvador. Rose W. I., Bommer J. J., Lopez D. L., Carr M. J., Major J. J. (eds), Natural Hazards in El Salvador. Bolder, Colorado, Geological Society of America Special Paper 375. pp. 109—120.