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Evolution of the H9N2 influenza genotype that facilitated the genesis of the novel H7N9 virus
Juan Pu, Shuoguo Wang, Yanbo Yin, Guozhong Zhang, Robert A. Carter, Jinliang Wang, Guanlong Xu, Honglei Sun, Min Wang, Chu Wen, Yandi Wei, Dongdong Wang, Baoli Zhu, Gordon Lemmon, Yuannian Jiao, Susu Duan, Qian Wang, Qian Du, Meng Sun, Jinnan Bao, Yipeng Sun, Jixun Zhao, Hui Zhang, Gang Wu, Jinhua Liu, and Robert G. Webster