A molecule-rich torus-like structure in the 21 µm source IRAS 23304+6147 Hao-Min Sun, Yong Zhang, Xu-Jia Ouyang, Sheng-Li Qin, Junichi Nakashima, Jian-Jie Qiu and Xiao-Hu Li A&A, 696 (2025) A102 Published online: 08 April 2025 DOI: 10.1051/0004-6361/202452355