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\bibitem{Karpov_etal2009} Karpov, A., Miller, D., Stern, J. A., Bumble, B., LeDuc, H. G., \& Zmuidzinas, J. (2009). Broadband SIS mixer for 1 THz Band. In \textit{Proc. 20$^{th}$ Int. Symp. Space Terahertz Technol.} (p. 35).

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