1N04:
reference: Structure of diferric hen serum transferrin at 2.8 A resolution., Guha Thakurta P, Choudhury D, Dasgupta R, Dattagupta JK, Acta Crystallogr D Biol Crystallogr 2003 Oct;59(Pt 10):1773-81. PMID: 14501117

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