7. REFERENCES
By the Global Warming Girls
http://library.thinkquest.org/J003411/causes.htm
By Greg Hennessey, Lavigne, and the Enlightenment
http://www.abelard.org/briefings/replacing_fossil_fuels.php#note_d
By the alternative energy group
http://www.altenergy.org/
By ABJT , written in July of 2009
http://answers.yahoo.com/question/index?qid=20090514221754AAS4TTN