Quasinormal modes and hidden conformal symmetry in the Reissner–Nordström black holeYong-Wan Kim, Yun Soo Myung and Young-Jai ParkEur. Phys. J. C, 73 5 (2013) 2440DOI: https://doi.org/10.1140/epjc/s10052-013-2440-8