Ultrahigh-energy gamma-ray emission associated with black hole–jet systems. - Cao, Zhen; Aharonian, Felix; Bai, Yun-Xiang; Bao, Yi-Wei; Bastieri, Denis; Bi, Xiao-Jun; Bi, Yu-Jiang; Bian, Wen-Yi; Bukevich, Anatoly V; Cai, Chengmiao (National Science Review, 2025)