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\bibitem{Gao_etal2018} {\textquotedblleft}\textit{Mode Transition of Filaments in Packed-Bed Dielectric Barrier Discharges}{\textquotedblright}. Gao M, Zhang Y, Wang H, Guo B, Zhang Q, Bogaerts A, Catalysts \textbf{8}, 248 (2018).   http://doi.org/10.3390/catal8060248

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