Abbott, Patrick L.,
Natural Disasters,
Fourth Edition, New York, NY, McGraw-Hill 2004.
del Moral, R. & S. Yu. Grishin, The consequences of volcanic eruptions,
L.R. Walker (ed.),
Ecosystems of Disturbed Ground
;
Ecosystems of the World
Series, D. W. Goodall Editor-in-Chief, Elsevier Science, Amsterdam, Chapter 5, 1999. http://faculty.washington.edu/moral/publications/RDM_Grishin.pdf
Herring, David. "Earth Observatory," from http://earthobservatory.nasa.gov/Library/Oven/
US Department of the Interior and US Geological Survey, "Water Science for Schools: The Water Cycle", August 2006, from http://ga.water.usgs.gov/edu/watercycle.html.
Wroble, Lisa,
Nature Recovers
, New York, NY, Newbridge Educational Publishing, 2003.