Xia, Ding, Qian, Xue, Han, Bai, Yang, Li, Belongie, Luo, Datcu, Pelillo, Zhang, Zhou, Yu, Hu, Bu, Tan, Yang, Li, Liu, Zhao, Ma, Gao, Wang, Zuo, Jiao, Meng, Wang, Wang, Hui, Dong, Zhang, Bao, Zhang, Liu, 2021. LUAI Challenge 2021 on Learning to Understand Aerial Images.