Research on the Improved Least Squares Reverse Time Migration Imaging MethodXiaodan Zhang, Dongxiao Liu, Guizhong Liu, Haiyang Gou, Rui Li, Zhiyu Zhang and Lin CuiE3S Web Conf., 236 (2021) 04017DOI: https://doi.org/10.1051/e3sconf/202123604017