Neutron-mirror neutron mixing and neutron stars Zurab Berezhiani, Riccardo Biondi, Massimo Mannarelli and Francesco Tonelli Eur. Phys. J. C, 81 11 (2021) 1036 Published online: 26 November 2021 DOI: 10.1140/epjc/s10052-021-09806-1