2OPC:
reference: The use of Co2+ for crystallization and structure determination, using a conventional monochromatic X-ray source, of flax rust avirulence protein., Guncar G, Wang CI, Forwood JK, Teh T, Catanzariti AM, Ellis JG, Dodds PN, Kobe B, Acta Crystallograph Sect F Struct Biol Cryst Commun. 2007 Mar 1;63(Pt, 3):209-13. Epub 2007 Feb 23. PMID: 17329816

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