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\bibitem{Gao_etal2006} Gao, J. R., Hajenius, M., Tichelaar, F. D., Voronov, B., Grishina, E., Klapwijk, T. M., et al. (2006). Can NbN films on 3C-SiC/Si change the IF bandwidth of hot electron bolometer mixers? In \textit{Proc. 17$^{th}$ Int. Symp. Space Terahertz Technol.} (pp. 187--189).

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