Radiating Kerr–Newman black hole in f(R) gravity Sushant G. Ghosh, Sunil D. Maharaj and Uma Papnoi Eur. Phys. J. C, 73 6 (2013) 2473 Published online: 18 June 2013 DOI: 10.1140/epjc/s10052-013-2473-z