In-depth investigation of the physical origin of the soft X-ray excess in PG 1448+273 Nan Ding, Qiusheng Gu, Yunyong Tang, Xue Ge, Xiaotong Guo, Xinpeng Xu, Yongyun Chen, Xiongfei Geng and JiaLi Liu A&A, 650 (2021) A183 Published online: 30 June 2021 DOI: 10.1051/0004-6361/202140848