A Single Amino Acid in the HA of pH1N1 2009 Influenza Virus Affects Cell Tropism in Human Airway Epithelium, but Not Transmission in Ferrets - van,Doremalen N; Shelton,H; Roberts,KL; Jones,IM; Pickles,RJ; Thompson,CI; Barclay,WS (PLOS ONE, 2011)