Polarized image of an equatorial emitting ring around a 4D Gauss–Bonnet black hole Xin Qin, Songbai Chen and Jiliang Jing Eur. Phys. J. C, 82 9 (2022) 784 Published online: 03 September 2022 DOI: 10.1140/epjc/s10052-022-10753-8