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\bibitem{Semenov_etal2007} Semenov, A., Richter, H., Smirnov, A., G{\"u}nther, B., H{\"u}bers, H. - W., Il{\textquoteright}in, K., et al. (2007). Development of HEB mixers for GREAT and for security screening. In \textit{Proc. 18$^{th}$ Int. Symp. Space Terahertz Technol.} (184).

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