Propagation of positive, negative, and recoil leaders in upward lightning flashes oleh XiuShu Qie, ShanFeng Yuan, HongBo Zhang, RuBin Jiang, ZhiJun Wu, MingYuan Liu, ZhuLing Sun, YunJiao Pu, JinLiang Li, Abhay Srivastava, ZiLong Ma, GaoPeng Lu