Occurrence and reassortment of avian influenza A (H7N9) viruses derived from coinfected birds in China -н Liu, W, Fan, H, Raghwani, J, Lam, T, Li, J, Pybus, O, Yao, H, Wo, Y, Liu, K, An, X, Pei, G, Li, H, Wang, H, Zhao, J, Jiang, T, Ma, M, Xia, X, Dong, Y, Zhao, T, Jiang, J, Yang, Y, Guan, Y, Tong, Y, Cao, W