Online Resources
Center for Educational Technologies: Earth’s Floor. http://www.cotf.edu/ete/modules/msese/earthsysflr/biomes.html
NASA Earth's Observatory: Mission Biomes. http://earthobservatory.nasa.gov/Experiments/Biome/
The University of California Museum of Paleontology: The World’s Biomes.http://www.ucmp.berkeley.edu/glossary/gloss5/biome/