3UYW:
reference: Structural vaccinology: structure-based design of influenza A virus hemagglutinin subtype-specific subunit vaccines., Xuan C, Shi Y, Qi J, Zhang W, Xiao H, Gao GF, Protein Cell. 2011 Dec;2(12):997-1005. Epub 2012 Jan 10. PMID: 22231357

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