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\bibitem{0kunev_etal1994} 0kunev, 0., Dzardanov, A., Ekstrom, H., Jacobsson, S., Kollberg, E., Gol{\textquoteright}tsman, G., et al. (1994). NbN hot electron waveguide mixer for 100 GHz operation. In \textit{Proc. 5$^{th}$ Int. Symp. Space Terahertz Technol.} (pp. 214--224).

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