Holographic Einstein rings of a Gauss–Bonnet AdS black hole Xiao-Xiong Zeng, Ke-Jian He, Jin Pu, Guo-Ping Li and Qing-Quan Jiang Eur. Phys. J. C, 83 10 (2023) 897 Published online: 05 October 2023 DOI: 10.1140/epjc/s10052-023-12079-5