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\bibitem{Darula_etal2000} Darula M, Semenov AD, H{\"u}bers H-W, Schubert J. Quasioptical high-T$_{c}$ superconductor Josephson mixer at terahertz frequencies [abstract]. In: Proc. 11$^{th}$ Int. Symp. Space Terahertz Technol.; 2000. 515.

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