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\bibitem{Treuttel_etal2009} Treuttel, J., Thomas, B., Maestrini, A., Wang, H., Alderman, B., Siles, J. V., et al. (2009). A 380 GHz sub-harmonic mixer using MMIC foundry based Schottky diodes transferred onto quartz substrate. In \textit{Proc. 20$^{th}$ Int. Symp. Space Terahertz Technol.}. Charlottesville, Virginia, USA.

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