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\bibitem{Villegas_etal2013} {\textquotedblleft}\textit{Sorting the modes contributing to guidance in strain-induced graphene waveguides}{\textquotedblright}. Villegas CEP, Tavares MRS, Hai G-Q, Peeters FM, New journal of physics \textbf{15}, 023015 (2013).   http://doi.org/10.1088/1367-2630/15/2/023015

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