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\bibitem{deSalas_etal2021} de Salas, P. F., Gariazzo, S., Martinez-Mirave, P., Pastor, S., \& Tortola, M. (2021). Cosmological radiation density with non-standard neutrino-electron interactions. \textit{Phys. Lett. B}, \textit{820}, 136508--9pp.

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