- https://capitolhillscience8.files.wordpress.com/2012/09/lithosphere.jpeg
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- http://newsoffice.mit.edu/sites/mit.edu.newsoffice/files/images/2010/20100427151320-1_0.jpg
- http://i.guim.co.uk/static/w-620/h--/q-95/sys-images/Guardian/Pix/pictures/2013/4/17/1366216777608/A-coal-fired-power-statio-011.jpg
- http://news.nationalgeographic.com/news/2007/09/photogalleries/animal-pictures/images/primary/1_461.jpg
- http://thewe.cc/thewei/&/&/images4/environment/trees_burn.jpe
- http://www.conservewildlifenj.org/images/artmax_161.jpg
- http://a.rgbimg.com/cache1nh0Vr/users/s/sc/scolpix/300/2dxruxJ.jpg
- http://studentaffairs.duke.edu/sites/default/files/u1379/ban_foam_graphic.png
- education.nationalgeographic.com/education/encyclopedia/biosphere/?ar_a=1
- gcs.k12.nc.us/cms/lib05/nc01000806/centricity/domain/501/human_impact_chapter_6.ppt
- sustain.wisconsin.edu/about-sustainable-management/
- ourworld.unu.edu/en/why-is-it-so-hard-to-save-thebiosphere