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\bibitem{Kong_etal2018} {\textquotedblleft}\textit{Topological Dirac semimetal phase in <tex> $Ge$_{x}$Sn$_{y}$ alloys}{\textquotedblright}. Kong X, Li L, Peeters FM, Applied physics letters \textbf{112}, 251601 (2018).   http://doi.org/10.1063/1.5037121

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