1CCF:
reference: How an epidermal growth factor (EGF)-like domain binds calcium. High resolution NMR structure of the calcium form of the NH2-terminal EGF-like domain in coagulation factor X., Selander-Sunnerhagen M, Ullner M, Persson E, Teleman O, Stenflo J, Drakenberg T, J Biol Chem 1992 Sep 25;267(27):19642-9. PMID: 1527084

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