Gaya APA

Casadevall, T, J. (1984). Crater Lake and Post-Eruption Hydrothermal Activity, El Chichon (April 1984). United States of America: U.S Geological Survey.

Gaya MLA

Casadevall, Thomas, J.. "Crater Lake and Post-Eruption Hydrothermal Activity, El Chichon". April 1984 United States of America: U.S Geological Survey, 1984. Text.