Multi-sensor comparison of aerosol optical properties profiles observed during a pollution episode in a mega city of the North China PlainLina Gao, Yong Zhang, Yubao Chen, Zhichao Bu, Xinghong Cheng, Junshan Jing and Shanshan LvE3S Web Conf., 194 (2020) 04059DOI: https://doi.org/10.1051/e3sconf/202019404059