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\bibitem{Borkowski_etal2021} {\textquotedblleft}\textit{FLCS-PON : a 100 Gbit/s flexible passive optical network: concepts and field trial}{\textquotedblright}. Borkowski R, Straub M, Ou Y, Lefevre Y, Jeli{\'c} {\v Z}L, Lanneer W, Kaneda N, Mahadevan A, Hueckstaedt V, van Veen D, Houtsma V, Coomans W, Bonk R, Maes J, Journal Of Lightwave Technology \textbf{39}, 5314 (2021).   http://doi.org/10.1109/JLT.2021.3102383

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