"459" . "Emergence and pandemic potential of swine-origin H1N1 influenza virus" . "10.1038/nature08157" . . . . "2009-06"^^ . _:b671308108 "2025-01-07T04:18:38.757956"^^ . . _:b671308108 . "939" . . "10.1038/nature08157" . _:b671308108 . "931" . _:b671308108 . . _:b671308108 . . . . "939" . . . "459" . . . _:b671308108 . . "10.1038/nature08157" . "Springer Science and Business Media LLC" . . "931" .