6NHP:
reference: Different genetic barriers for resistance to HA stem antibodies in influenza H3 and H1 viruses., Wu NC, Thompson AJ, Lee JM, Su W, Arlian BM, Xie J, Lerner RA, Yen HL, Bloom JD, Wilson IA, Science. 2020 Jun 19;368(6497):1335-1340. doi: 10.1126/science.aaz5143. PMID: 32554590

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