4AVG:
reference: Structural Analysis of Specific Metal Chelating Inhibitor Binding to the Endonuclease Domain of Influenza pH1N1 (2009) Polymerase., Kowalinski E, Zubieta C, Wolkerstorfer A, Szolar OH, Ruigrok RW, Cusack S, PLoS Pathog. 2012 Aug;8(8):e1002831. Epub 2012 Aug 2. PMID: 22876177

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