References

Dann, J. (2010). Thin section image of Garnet Mica Schist from Salangen, Norway [Digital image]. Wikimedia Commons. https://commons.wikimedia.org/wiki/File:Thin_section_of_garnet-mica-schist.jpg

Egger, J. (2013). Heather soil profile from Badgworthy Hill, Devon, England [Digital photo]. Wikimedia Commons. https://commons.wikimedia.org/wiki/File:Heather_soil_profile,_Badgworthy_Hill,_Devon,_England_(close-up).JPG

Simmon, R., & Allen, J. (2011). The big muddy, Western edition [Digital photo]. NASA’s Earth Observatory. http://earthobservatory.nasa.gov/IOTD/view.php?id=77368.