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De La Fuente, Jesus. "Graphene - What Is It?" Graphenea. N.p., n.d. Web. 27 May 2015. <http://www.graphenea.com/pages/graphene#.VWVYiFnBzGc>.
"The Home of Graphene." The Home of Graphene. University of Manchester, n.d. Web. 27 May 2015. <http://www.graphene.manchester.ac.uk/explore/the-questions-everyones-asking/>.
Limer, Eric. "Graphene's Newest Trick Is Improving Your Tennis Game." Gizmodo. Gizmodo, 1 Nov. 2013. Web. 27 May 2015. <http://gizmodo.com/5975246/graphenes-newest-trick-is-improving-your-tennis-game>.