Morris, J. D., & Austin, S. A. (2003). Footprints in the ash: The explosive story of Mount St. Helens. Master Books.
Lua i Stíl Chicago (17ú heag.)Morris, John D., agus Steven A. Austin. Footprints in the Ash: The Explosive Story of Mount St. Helens. Green Forest, AR: Master Books, 2003.
Lua MLA (9ú heag.)Morris, John D., agus Steven A. Austin. Footprints in the Ash: The Explosive Story of Mount St. Helens. Master Books, 2003.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.