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\section*{1998}

Yazoubov P, Kroug M, Merkel H, Kollberg E, Gol{\textquoteright}tsman G, Lipatov A, et al. Quasioptical NbN phonon-cooled hot electron bolometric mixers with low optimal local oscillator power. In: Proc. 9$^{th}$ Int. Symp. Space Terahertz Technol.; 1998. p. 131--40.

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