Gravitation field perturbation quasinormal modes of a black hole in F(R) gravity Keramat Malekmakan, Reza Saffari, Saheb Soroushfar and Behnam Pourhassan Eur. Phys. J. Plus, 137 11 (2022) 1255 Published online: 17 November 2022 DOI: 10.1140/epjp/s13360-022-03441-9