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\bibitem{Belitsky_etal2011} Belitsky V, Desmaris V, Dochev D, Meledin D, Pavolotsky A. Towards Multi-Pixel Heterodyne Terahertz  Receivers. In: Proc. 22$^{th}$ Int. Symp. Space Terahertz Technol.; 2011.

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