Bibliography
Cover Page:
Swamp - http://itbbs.pconline.com.cn/soft/11393290.html
Mountains - http://www.wallpaperpics.net/wallpaper/big-mountain-wide.html
Snow Trees - http://www.earthzine.org/2012/05/25/forest-carbon-research-in-ireland-the-importance-of-long-term-monitoring-of-forest-growth-and-climate/
Desert - http://tourists360.com/sahara-desert/
Ocean - http://www.wwf.org.nz/?4780/The-Life-Aquatic
Forest - http://www.ecotrust.org
Flower Field - http://www.hdwallpapersin.com/flowers/oldest/8
Evolution of Men - http://ameblo.jp/veganstyle/entry-11830855900.html
Pills - http://www.kanald.ro/Atentie-antibiotice-Vezi-impact-asupra-organismului-VIDEO_13523.html
Mammoth - http://galleryhip.com/saber-tooth-tiger-painting.html
Back Page - http://www.wallpapermania.eu/wallpaper/ocean-versus-desert-greened-tree-versus-dry-tree
Bibliography - http://wall.alphacoders.com/by_sub_category.php?id=173995
rt - http://tourists360.com/sahara-desert/