Cita APA (7th ed.)

Morris, J. D., & Austin, S. A. (2003). Footprints in the ash: The explosive story of Mount St. Helens. Master Books.

Cita Chicago (17th ed.)

Morris, John D., i Steven A. Austin. Footprints in the Ash: The Explosive Story of Mount St. Helens. Green Forest, AR: Master Books, 2003.

Cita MLA (9th ed.)

Morris, John D., i Steven A. Austin. Footprints in the Ash: The Explosive Story of Mount St. Helens. Master Books, 2003.