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\bibitem{Grimes_etal2003} Grimes, P., Kittara, P., Yassin, G., Withington, S., \& Jacobs, K. (2003). Investigation of the performance of a 700 GHz nline mixer. In \textit{Proc. 14$^{th}$ Int. Symp. Space Terahertz Technol.} (247). Tucson, USA.

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