Sources

"Geothermal Energy Environmental Benefits." - Halliburton. N.p., n.d. Web. 19 May 2016.

"Geothermal Energy Pros and Cons - Energy Informative." Energy Informative. N.p., n.d. Web. 19 May 2016.

"Geothermal Energy." Technology. N.p., n.d. Web. 17 May 2016.

"Te Ara Encyclopedia of New Zealand." 5. – Geothermal Energy –. N.p., n.d. Web. 19 May 2016.