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\bibitem{Smirnov_etal2003} Smirnov, K. V., Vachtomin, Y. B., Antipov, S. V., Maslennikov, S. N., Kaurova, N. S., Drakinsky, V. N., et al. (2003). Noise and gain performance of spiral antenna coupled HEB mixers at 0.7 THz and 2.5 THz. In \textit{Proc. 14$^{th}$ Int. Symp. Space Terahertz Technol.} (pp. 405--412).

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