Neutrino masses and Hubble tension via a Majoron in MFV Fernando Arias-Aragón, Enrique Fernández-Martínez, Manuel González-López and Luca Merlo Eur. Phys. J. C, 81 1 (2021) 28 Published online: 15 January 2021 DOI: 10.1140/epjc/s10052-020-08825-8