2DFP:
reference: Crystal structures of aged phosphonylated acetylcholinesterase: nerve agent reaction products at the atomic level., Millard CB, Kryger G, Ordentlich A, Greenblatt HM, Harel M, Raves ML, Segall Y, Barak D, Shafferman A, Silman I, Sussman JL, Biochemistry 1999 Jun 1;38(22):7032-9. PMID: 10353814

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