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\bibitem{Semenov_etal2003} Semenov AD, Hiibers H-W, Richter H, Smirnov K, Gol{\textquoteright}tsman GN, Kaurova N, et al. Superconducting hot-electron bolometer mixer for terahertz heterodyne receivers. In: Proc. 14$^{th}$ Int. Symp. Space Terahertz Technol.; 2003. p. 33--40.

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